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Characterization and focusing of capillary-discharge XUV-laser beam for purposes of thin-film deposition
Pira, Peter ; Wild, Jan (advisor)
Title: Characterization and focusing of capillary-discharge XUV-laser beam for purposes of thin-film deposition Author: Peter Pira Department: Department of Surface and Plasma Science Supervisor: doc. RNDr. Jan Wild, CSc., Department of Surface and Plasma Science Abstract: The paper deals with the first results of the interaction of a desk-top high repetition rate XUV laser (wavelength of 46.9 nm) radiation with materials suitable for optoelectronics, in particular the ionic crystals CsI, LiF, etc. Using surface physics methods (AFM, DIC Normanski microscopy) pulse laser imprints were investigated. Based on the results obtained, general information on the nature of ablation and desorption was obtained, which were compared with the results of the XUV-ABLATOR modified code modeling. Plasma arising from ablation was examined by a modified Langmuir probe system. The main result is the pulse laser deposition of thin films of Bi and CsI. Keywords: ablation, Pulsed Laser Deposition, XUV laser
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Conductive model of human tissue for electroporation purposes
Zelinková, Kateřina - Šarlota ; Cipín, Radoslav (referee) ; Novotná, Veronika (advisor)
This thesis solves the issue of the distribution of the high voltage pulse at the electroporation of the arget ablation zone. For futher examination of influence electroporation was necessary to first understand theoretically electrical charakter of cells and replace with basics eletrical circumferential elements (RLC). Based on this knowledge, theoretical prerequisites for experimental measurements were derived. Theoretical assumptions were then verified by experimental measurements. In the measurement, the assumptions found were confirmed, but significant performance losses were identified. A new catheter was designed to reduce the loss. Because the production of a new catheter is not economically disadvantageous, the properties of the new catheter were first tested using the simulation cloud environment SIMSCALE, where the heating of the heart tissue after the application of the electroporation pulse was monitored. Furthermore, the electroporation process was simulated in the FEMM program, where emphasis was placed on the propagation of cardiac tissue tension.
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EKG synchonization of electroporation pulses
Nohel, Michal ; Mézl, Martin (referee) ; Novotná, Veronika (advisor)
Bachelor thesis is focused on cells electroporation principle and its types. It further describes thermal and nonthermal ablation techniques with an emphasis on irreversible electroporation. It contains an overview of fields, where medical procedures in combination with ECG signal are used, and an overview of techniques and measurements of the electrocardiographic signal. Further, the sensitivity of the human body to electroporation pulses is discussed. During electroporation, short high-voltage pulses are applied. Ventricular fibrillation may occur if the electroporation pulse is applied to the vulnerable period of the heart rhythm. Synchronization of pulse application with heart activity of the patient is necessary for health and safety reasons in clinical practice. The practical part of the thesis is about a LabVIEW program for this kind of synchronization. The created program is tested and the obtained results achieved are evaluated in terms of practical use.
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Characterization and focusing of capillary-discharge XUV-laser beam for purposes of thin-film deposition
Pira, Peter ; Wild, Jan (advisor) ; Čuba, Václav (referee) ; Tichý, Milan (referee)
Title: Characterization and focusing of capillary-discharge XUV-laser beam for purposes of thin-film deposition Author: Peter Pira Department: Department of Surface and Plasma Science Supervisor: doc. RNDr. Jan Wild, CSc., Department of Surface and Plasma Science Abstract: The paper deals with the first results of the interaction of a desk-top high repetition rate XUV laser (wavelength of 46.9 nm) radiation with materials suitable for optoelectronics, in particular the ionic crystals CsI, LiF, etc. Using surface physics methods (AFM, DIC Normanski microscopy) pulse laser imprints were investigated. Based on the results obtained, general information on the nature of ablation and desorption was obtained, which were compared with the results of the XUV-ABLATOR modified code modeling. Plasma arising from ablation was examined by a modified Langmuir probe system. The main result is the pulse laser deposition of thin films of Bi and CsI. Keywords: ablation, Pulsed Laser Deposition, XUV laser
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Double pulse capillary discharge assessment for nitrogen soft X-ray laser.
Hübner, Jakub ; Nevrkla, M.
The work examines possibilities of capillary discharge pinching plasma driven by combination of two electric current pulses ("pedestal" slow exponentially damped sinus t1/4 > 200 ns, peak current Ipeak < 50 kA and fast triangular pulse with a rise time about 38 ns, Ipeak > 60 kA) to obtain the maximum possible gain at wavelength l = 13.4 nm (hydrogen-like nitrogen recombination scheme). The optimal initial density ρ0 (or pressure) and start time tstart of second triangular pulse (second pulse start at peak current Ipeak of the first pulse) were determined for two capillary radii (0.5 and 1 cm) and four current peaks of the first pulse (20, 30, 40 and 50 kA).\n
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High Voltage Pulse Generator for Electroporation of Cells
Puczok, Václav ; Martiš, Jan (referee) ; Červinka, Dalibor (advisor)
The main goal of this thesis is to design control board for the experimental electroporation device and to develop control firmware. The first chapter of this work focuses on the electroporation phenomenon itself. Behaviour of the cell model in external electrical field is described there as well as simulation and overview of how electroporation affects living tissue. It also explains the main requirements for parameters of the electroporation pulses as well as need for ECG synchronization. Furthermore, some remarks are given about novel high frequency electroporation method, which involves use of nanosecond bipolar high voltage pulse bursts. The second chapter briefly introduces commercial electroporation device called Nanoknife, including control part, power part, and it's limits. The third chapter consists of introduction of the novel experimental electroporation device developed at BUT. Power part of this device is discussed as well. Next chapter focuses on design of the control board for this device and also on description of the particular schematic parts. There is a control algorithm explanation in the fifth chapter of this thesis followed by the brief manual to machine operation.
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