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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Metody depozice tenkých vrstev pomocí nízkoteplotního plazmatu / Deposition methods of thin films using low-temperature plasma

GÜNZEL, Martin January 2013 (has links)
This thesis is focused on the description of selected deposition methods of thin films using low-temperature plasma. Currently, many various technologies of thin films are developed and there are many applications in various industrial sectors. This thesis first gives a brief overview of deposition methods, plasma behavior during deposition and subsequent description of the selected methods of application due to the physical and chemical processes. They also discussed the advantages and disadvantages of the described coating technologies, and several examples of their use. The thesis should thus contribute to the overall view of modern coating technologies, their development and use currently, or possible use in the future.
112

Stravovací návyky a pitný režim dárců krevní plazmy před plazmaferézou / Donor eating habits and drinking schedule before plasmapheresis

Hostinová, Alena January 2018 (has links)
(thesis): Basis: This diploma thesis follows the bachelor thesis that concentrates on the eating habits and water intake of blood plasma donors before plasmapheresis. Goals: The research had four goals: 1) explore to what extent does providing of the educational material influence the awareness of blood plasma donors. 2) To map subjective state of health and lifestyle of plasma donors regarding their physical activity, healthy, regular, varied diet, smoking and sleep schedule. 3) To explore the knowledge of regime measures and risk behaviour before donating blood plasma. To evaluate donors' eating habits and water intake before plasmapheresis and reveal potential deficiencies. 4) Evaluate the knowledge of a given problem with those respondents who were provided with educational material in comparison with those respondents who got no educational material. Methods: An educational material was created regarding regime measures of blood plasma donors. This educational material served as the basis for standardized anonymous questionnaire. Maintaining the ethical principles and with the ethical committee's approval, overall data of 40 respondents frequenting Haematology Department and blood transfusion of the Military University Hospital Prague. The sample consisted of two groups of randomly selected...
113

Optimalizace sítě transfúzních míst v České republice / Network Optimization of Transfusion Sites in the Czech Republic

Konderlová, Nicolle January 2015 (has links)
This thesis is about medical transfusion sphere, which has nowadays many deficits - as the other spheres in medical industry. Target of this thesis is a proposal of new equipment structure in transfusion service in the Czech Republic, which will be more effective then the existing one and which occurs a reduction of blood processing department. It includes not only calculation of basic expenses needed for installation new system and ensure operations for 5 years and comparison of both variants, but it includes also proposal of centralized managing and changes of staff secure of production process.
114

Fosfan a oxid dusný jako falešně pozitivní biosignatury ve spektrech planet / Phosphine and nitrous oxide as false-positive biosignature gases in planetary spectra

Kaiserová, Tereza January 2021 (has links)
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...
115

Parametry laserového paprsku / Parameters of the laser beam

Hort, Zbyněk January 2017 (has links)
The diploma thesis consists of the three main parts. The first part deals with the theoretical description of the laser technology and other unconventional technologies. In the second part, the thesis is focused on testing the parameters of the laser and evaluating the most suitable parameters. In the last part the diploma thesis deals with comparison of unconventional technologies in terms of cut quality
116

Plasmochemické úpravy oxidických polovodičových fotoanod / Plasmochemical treatment of photoanodes with semiconducting oxide layer

Ďurašová, Zuzana January 2018 (has links)
This diploma thesis deals with a plasmochemical treatment of photoanodes with an active layer containing TiO2 deposited on two different substrates by material printing. The plasmochemical treatment was performed by a low-temperature ambient-air plasma using a diffuse coplanar surface barrier discharge (DCSBD). The experimental part is focused on the investigation of DCSBD influence on the fabricated photoanodes photoelectrochemical properties, and the influence of plasma treatment time. Process optimization was achieved by height adjustment of the electrode. The processed coatings were electrochemically investigated by linear sweep voltammetry and chronoamperometry.
117

Modul pro detekci lehkých prvků v železných slitinách metodou spektroskopie laserem buzeného plazmatu / Module for the detection of light elements in ferrous alloys by the Laser-Induced Breakdown Spectroscopy technique

Hrabal, Zdeněk January 2018 (has links)
Tato diplomová práce je zaměřena na analýzu lehkých prvků (tj. uhlík, sýra a fosfor) v železných slitinách pomocí metody laserem indukovaného plazmatu (LIBS). Hlavním cílem je vyvinout a implementovat nový modul, který bude umožňovat analýzu v hluboké ultrafialové oblasti (VUV), což je nezbytné jak pro stanovení chemického složení lehkých prvků v ocelích tak pro mnoho dalších aplikací metody LIBS. V první části je vytvořen přehled moderních přístupů optické emisní spektroskopie (OES) a rovněž jsou shrnuty tradiční techniky používané v metalurgii pro analýzu ocelí. Teorie absorpce ultrafialového záření vzduchem a optickými skly byla důkladně studována a shrnuta k získání potřebného teoretického základu k vývoji modulu. Před návrhem finální verze modulu byl navržen experimentální modul s cílem otestovat navržený koncept analýzy ve VUV oblasti metodou LIBS. Na základě testování byla navrhnuta finální verze založená na unikátním klínovém mechanismu. Funkční vzorek byl vyroben ve spolupráci s extérním výrobcem a vlastnosti modulu byly následně demonstrovány naměřením pěti certifikovaných ocelových standardů. Experiment určil limity detekce pro uhlík jako 0.028 hm.%. Nicméně, síra ani fosfor nebyly detekovány v žádném ze vzorků. Tato práce vytvořila modul nezbytný pro budoucí zkoumání metody LIBS v oblasti VUV v Laboratoři laserové spektroskopie v Brně.
118

Funkční organicko-anorganické nanostruktury / Functional organic-inorganic nanostructures

Kelíšek, Petr January 2019 (has links)
Diploma thesis deals with preparation of multilayered organic-inorganic nanostructures via PECVD technology and analysis of optical properties of these layers by spectroscopic ellipsometry. The theoretical part handles the definition of thin layers, layered and gradient nanostructures, plasma enhanced chemical vapor deposition and principles of spectroscopic ellipsometry. In the experimental part, used materials and chemicals are described, afterwards follow a complete description of the apparatus used for sample preparation and a description of the sample preparation procedure. The results part consists of methodology of preparing material models necessary for ellipsometric measurements and evaluation of optical properties of deposited nanolayers.
119

Plazmochemické odstraňování korozních vrstev bronzu / Plasma chemical removal of bronze corrosion layers

Miková, Petra January 2019 (has links)
The thesis deal with applying low-pressure low-temperature plasma to corrosion products layers on bronze. Layers of corrosion products on samples were artificially prepared. As a result, they had the same composition and could be irreversibly destroyed during experiments, which would not be possible with real archeological artifacts. Bronze, copper and tin alloy, samples were cut with respect to the size of the plasma-chemical device. XRF was used to determine the bronze composition. Before being corroded by the active medium, each sample was washed with ethanol and dried with a hot air stream. Until now, the procedure was the same for all samples. During formation of corrosion products layers, two factors have to be taken into account: the time consumption and the corrosiveness of the active environment. By focusing on one or the other factor, several groups of samples with differently degraded surfaces were created. The fastest way was to place samples in a corrosion chamber where sodium chloride solution was applied at the elevated temperature. The samples were corroded within a few days there. Longer, but in terms of corrosion products layers compactness better way proved procedure where the samples were sealed in the desiccator. At the desiccator bottom the Petri dish with an inorganic acid was placed, in our case, with hydrochloric acid inside. This method corroded the samples within one month. The longest but the most closed to the real live method was the burial of samples into soil or compost. However, this method corroded the samples within two years. Final step after the samples were removed from any corrosive environment, were dried under low pressure and were placed in a barrier film made bag together with moisture and oxygen absorbers. So prepared samples with layers of corrosion products have been treated in a low-pressure low-temperature plasma. Treatment was carried out in the apparatus which is based on the reactor: cylinder of quartz glass having a diameter of 100 mm and a length of 900 mm. The reactor was supplied with a working gas or a mixture of working gases with a total flow rate of 50 sccm. In our case, one is pure hydrogen or a combination with argon. A rotary oil pump was used to provide vacuum. The reactor base pressure was 10 Pa before treatment, while during the treatment it was 150 Pa. High-frequency generator (13.54 MHz) was used for supply the system with energy through two copper electrodes located outside the reactor. According to the energy delivery method, the treatment was carried out in a continuous or pulse mode. The sample temperature was monitored during the experiment and were evaluated the emission spectra from OES. The sample temperature was one of the key factors. The measurement was first done with a thermocouple, later switched to a thermocouple with optical data transmission. A safe temperature was set and then the whole process was controlled through it. In addition, the effect of the energy delivery method, value of the delivered power, sample size, presence of incrusted layers and composition of working gas were studied. After application of plasma, samples were analyzed by SEM – EDX and XRD. After the evaluation of the acquired knowledge and experience, a real artifact - a bronze chisel from the site of Boskovice - was treated. This documentation lacked the artifact, so it could be used to verify the lessons learned about plasma chemical reduction.
120

Příprava a charakterizace plazmatem aktivované vody pro využití v bioaplikacích / Preparation and characterization of plasma activated water for bio applications

Lemonová, Hana January 2020 (has links)
The aim of this master thesis is the preparation and characterization of plasma activated water (PAW) prepared by dielectric barrier discharge at atmospheric pressure in air for the future applications in agriculture and medicine. The theoretical part is focused on plasma activated water and its effects on seeds and plants. The work also deals with the preparation and application of PAW in the world. Various types of plasma discharge configurations suitable for its preparation are described here. In the experimental part of the master thesis, distilled and tap water were chosen for activation. The concentrations of active particles in PAW generated by DBD such as nitrites, nitrates and hydrogen peroxide were determined. The value of the concentration of active particles changes probably due to mutual interactions when nitrites are oxidized by hydrogen peroxide to nitrates. Physical properties of PAW such as conductivity and pH were also characterized. After the preparation of PAW, the conductivity increases due to the increase in the concentration of active particles formed by dissociation and ionization of water molecules by plasma. The particles presented in the air, which are dissociated and ionized by plasma, also diffuse into the liquid, and contribute to this increase. The decrease in pH also corresponds to an increase in the concentration of hydrogen ions and the formation of nitric acids. Another aspect of this work was to study plasma activated water during the first eight hours after its preparation and to determine its properties. We have found that PAW prepared from tap water retains its characteristic properties for at least 8 hours and distilled water for 6 hours. In the master thesis, the analysis of plasma discharge was performed using optical emission spectroscopy. OES measurements were performed in the wavelength range 300 to 800 nm. The second positive nitrogen system (N2 (C 3u) N2 (B 3g)) and the first positive nitrogen system (N2 (B 3g) N2 (A 3+u)) were identified in the overview spectrum. Molecular nitrogen ions, OH· radicals, atomic oxygen and atomic hydrogen can be observed in the spectrum, too. The dielectric barrier discharge was also captured using a high-speed camera, and the recording shows the occurrence of multiple discharges that are spatially as well as temporary unstable.

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