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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.
91

Cílené biokompatibilní nanočástice pro terapii a diagnostiku rakoviny. / Targeted biocompatible nanoparticles for therapy and cancer diagnostics.

Neburková, Jitka January 2018 (has links)
Nanoparticles (NPs) have considerable potential in targeted medicine. NPs can merge various functions and serve as labels for imaging or as nanocarriers in therapy. Modification of NPs with targeting ligands can lead to highly specific interactions with targeted cancer cells. However, the efficacy of targeting depends on the ratio between specific and non-specific interactions of a NP with the cell. Non-specific interactions of NPs are unrelated to targeted receptors and need to be eliminated in order to decrease background noise during imaging and adverse effect of drugs on healthy tissues. In this thesis, surface modifications of NPs were explored mainly on biocompatible carbon NPs called nanodiamonds (NDs), which have exceptional fluorescent properties such as long fluorescence lifetime, no photobleaching and photoblinking and sensitivity of their fluorescence to electric and magnetic field. Main issues addressed in this thesis are low colloidal stability of NDs in buffers and media, their non-specific interactions with proteins and cells and limited approaches for ND surface modifications. These issues were solved by coating NDs with a layer of biocompatible, hydrophilic, and electroneutral poly(ethylene glycol) or poly[N-(2- hydroxypropyl) methacrylamide] polymers. Optimized polymer coating...
92

Molekulové mechanismy homocystinurie: prostorové uspořádání lidské cystathionin β-synthasy / Molecular mechanisms in homocystinuria: spatial arrangement of human cystathionine β-synthase

Hnízda, Aleš January 2012 (has links)
Protein misfolding is considered to be the major pathogenic mechanism in homocystinuria due to cystathionine beta-synthase (CBS) deficiency. The aim of this work was to study molecular mechanisms underlying protein misfolding of CBS mutants. Firstly, we studied spatial arrangement of normal human CBS protein. Using data from differential covalent labeling of solvent-exposed aminoacid residues, we identified interdomain contact area between the catalytic core and the regulatory domain in human CBS, and we subsequently generated the structural model of the full-length CBS. In the next step, we studied evolutionary divergence of CBS protein structures. We performed phylogenetic analysis that revealed unique spatial arrangement of CBS enzyme in nematodes; the domain architecture of CBS in Caenorhabditis elegans was studied experimentally in more detail. Finally, we determined conformational properties of a representative set of human CBS mutants that exhibited in various extent affected formation of tetramers and decreased catalytic activity. Using thermolysin-based proteolytic techniques for analysis of nine mutants expressed in E.coli, we found that an unfolded structure is a common intermediate occurring in CBS misfolding. The importance of protein unfolding for pathogenesis of CBS deficiency was...
93

In-situ studium změny topografie třecích povrchů v elastohydrodynamickém kontaktu / In-situ Study of Surface Topography Changes in Elastohydrodynamic Contact

Šperka, Petr January 2011 (has links)
This dissertation thesis deals with elastohydrodynamic lubrication (EHL) of surfaces with real roughness. Systematic study of surface harmonic components behaviour, during their passage of the EHL contact, by other authors led to retrieval of a uniform principle according which individual harmonic components deform inside the contact. Although the amplitude attenuation model can provide rapid tool for more accurate surface assessment in design process it has not been validated on real surfaces till now. The thesis represents pioneering work on quantitative analysis of real surfaces EHD measurements. It contains original and new results with real and model roughness features that in many cases confirm theoretical expectations. Deeper understanding of surface roughness behaviour inside EHL contact, which is typical for machine parts like bearings, gears, cams etc., can help to improve design process of the components and ultimately enable machines and equipment to work with lower energy requirements and higher durability.
94

Systematická povrchová prospekce v jižním Uzbekistánu / Systematical Field Survey in South Uzbekistan

Tušlová, Petra January 2012 (has links)
The following thesis summarizes two years investigation conducted in Sherabad District in South Uzbekistan. The research was focused on systematic field survey in immediate vicinity of tepas, artificial mounds created by centuries of a human inhabitation. Five different areas were examined in order to follow the settlement extant and chronology. The work was conducted by using satellite imageries in combination with topographical maps. The information collected on the fields were marked in PDA running GIS application and evaluated in computer. The results of the field prospection were verified by using complementary methods of the test pits and of the total pickups. Key words: Central Asia, South Uzbekistan, Sherabad District, topographical maps, satellite imagery, systematic field survey, test pits, total pickups, GIS application.
95

Analýza a inverze povrchových vln - aplikace na Český masiv / Surface Wave Analysis and Inversion-Application to the Bohemian Massif

Kolínský, Petr January 2010 (has links)
title: Surface Wave Analysis and Inversion Application to the Bohemian Massif author: Mgr. Petr Kolínský, DiS. author's e-mail address: kolinsky@irsm.cas.cz departments: Department of Geophysics Faculty of Mathematics and Physics Charles University Prague V Holešovičkách 2, Praha 8 - 180 00, Czech Republic and Department of Seismology Institute of Rock Structure and Mechanics, v.v.i. Academy of Sciences of the Czech Republic V Holešovičkách 41, Praha 8 - 182 09, Czech Republic supervisor: RNDr. Johana Brokešová, CSc. supervisor's e-mail address: johana.brokesova@mff.cuni.cz consultant: RNDr. Jiří Málek, PhD. consultant's e-mail address: malek@irsm.cas.cz keywords: surface waves, group velocity, phase velocity, frequency-time analysis, multiple filtering, tomography, inversion problems, Earth crust structure, Bohemian Massif An overview of surface wave analysis methods as well as of inversion techniques is given. Special attention is paid to the multiple filtering method for dispersion curve estimation, which is described by two different ways in detail. The isometric method is used for dispersion curve inversion and its description and tests are presented. Described methods are further used in applications. The applications show examples of surface wave analysis and inversion for 1D and 2D...
96

Vývoj osídlení v mikroregionu Zarabag (jižní Uzbekistán) na základě archeologických pramenů / Dynamics of the settlement pattern in the microregion of Zarabag (southern Uzbekistan) on the basis of archaeological sources

Augustinová, Anna January 2017 (has links)
15 Abstract The following thesis summarizes results of the archaeological research in the microregion of the Zarabag Oasis in the South Uzbekistan. The non-destructive research focused on the collection and evaluation of the archaeological data that allow to reconstruct the settlement dynamics in the oasis during the ages. Previously, there was not archaeological evidence available in the region. The fieldwork in the oasis and its closest surroundings was conducted by way of extensive surface survey (global coverage of the oasis focused on the detection of archaeological evidence), and intensive one (systematic surface survey on a closely defined area). The extensive survey proved to be more suitable for the studied environment in terms of the quality and quantity of the collected archaeological data. One part of the survey consisted in detection of the water sources (springs, surface canals and even remains of the karez systems). The basic units of extensive survey were represented by polygons (gardens, fields, cemeteries, tepas etc.), to which the finds collected during the research were attributed. Their dating in the combination with their spatial distribution allowed then to reconstruct the settlement processes and dynamics in the microregion of the oasis. One part of the research deals also with the...
97

Flotace rozpuštěným vzduchem – od poloprovozního modelu po plnou realizaci / Dissolved Air Flotation – From Pilot Plant to Full Scale Implementation

Dobiáš, Pavel January 2018 (has links)
The thesis deals with the use of dissolved air flotation (DAF) in water treatment technology in the Czech Republic. It summarizes the knowledge gained at pilot plant studies as well as the experience with full-scale flotation units which have been built in potable water treatment plants in the Czech Republic in years 2006-2018. This thesis provides a broad background of experimental studies of a modern separation process, which does have great advantages in the removal of natural organic matter and microorganisms from water in the drinking water treatment industry. In this thesis, there are presented some examples of the excellent efficiency of the microorganisms removal, both under the experimental conditions as well as water treatment plants, which were improved by DAF units installation in full scale. In addition to the high separation efficiency, it is shown, how DAF units could influence the subsequent separation steps as for example filtration through the granular media. The negative influence of the pre-ozonization on the DAF separation efficiency in Hradec Králové WTP is demonstrated too. The results of the pilot experiments support the idea, that the key condition for high removal efficiency is the optimal coagulation process chemistry. Design of pilot experiments was based on the factorial planning theory and some results are discussed in this thesis. The very big portion of the pilot experiments was made for estimating of the full-scale DAF design parameters before the water treatment plants reconstruction phase
98

Příprava a strukturní stabilita nanokrystalických tepelných bariér / Processing and Structural Stability of Nanocrystalline Thermal Barrier Coatings

Jech, David January 2018 (has links)
Complex thermal barrier coating systems are one the most efficient high-temperature surface treatments which open up practical applications in land-based turbines and air jet engines. In the case of most exposed rotor and stator jet engine components, the combination of thermal barrier coatings together with the inner cooling system made it possible to increase working temperature by several tens of degrees of Celsius. Nevertheless, it is very difficult to achieve any further increase in working temperature by using the conventional thermal barrier coatings based on the ZrO2-Y2O3 ceramic top coat and the MCrAlY metallic bond coat, which currently work at their material limits. The working temperature inside the combustion chamber of the jet engine is proportional to engine’s efficiency and inversely proportional to fuel consumption and production of undesirable CO2 emission. Therefore, a considerable effort has recently been devoted to research and development of new types of ceramic coatings that can withstand long term extreme working conditions. New design approaches of multi-layer composite thermal barrier coating systems can sustain the required trend of increasing working temperature of jet engines mainly because of possibility of optimization of high-temperature durability and long lifetime. The theoretical part of thesis provides a fundamental overview of thermal barrier coatings, their properties, deposition technologies and testing methods. The experimental part is focused on optimization of deposition parameters of conventional ZrO2-Y2O3 / MCrAlY thermal barrier coatings prepared by means of atmospheric plasma spraying. Furthermore, a novel multi-layer thermal barrier coating system based on ZrO2-Y2O3-Al2O3-SiO2 / ZrO2-Y2O3 / MCrAlY, which contains amorphous and/or nanocrystalline regions, is developed, tested and characterized as well. Structural stability, phase transformations and growth of the thermally grown oxide in both conventional and experimental systems after high-temperature isothermal oxidation, cyclic oxidation and burner-rig tests were evaluated by means light microscopy, scanning electron microscopy with energy-dispersive microanalysis and X-ray diffraction. In comparison with the conventional thermal barrier coatings, the novel multi-layered systems have lower thermal conductivity, slower thermally grown oxide kinetic, better structural stability, and generally higher lifetime in all high-temperature tests.
99

Návrh a posouzení suché nádrže a protipovodňové ochrany / Design of small reservoirs and flood protection

Pikna, Martin January 2019 (has links)
The diploma thesis deals with the design of the flood protection of the village Hrušky (Vyškov district). The hydraulic analysis of the water flow on the rivers Litava (river station km 19,460 - 20,928) and Rakovec (river station km 0,000 - 0,638) was done. The hydraulic analysis was performed on the Q5, Q20 and Q100 flows. For analysis was used a 2D numerical flow model in HEC-RAS 5.0.6. Based on results was designed a flood protection including a dry reservoir. The input data for the diploma thesis was the 2013 study „Litava II – přírodě blízká protipovodňová opatření a obnova přirozené hydromorfologie a retenční kapacity toku a nivy v úseku ř. km 16,0 (Újezd u Brna) až ř. km 24,0 (Slavkov u Brna)“. The diploma thesis was processed as a real project in the design office of Regioprojekt Brno, s.r.o.
100

Měření povrchového napětí pro charakterizaci povrchů pokročilých keramických materiálů / Measurement of surface tension for surface characterization of advanced ceramic materials

Mišáková, Liliana January 2020 (has links)
Povrchy inorganických materiálov, zvlášť kovov alebo kovových oxidov, ktoré sú často charakteristické vysokou povrchovou energiou, sú zvyčajne kontaminované adsorbovanými organickými molekulami. Tieto molekuly majú na povrchy zväčša nepriaznivý vplyv, do značnej miery napríklad ovplyvňujú funkcionalitu a výkonnosť polovodičov a znemožňujú, prípadne sťažujú prevedenie povrchových úprav na povrchoch kovov aj keramík. Taktiež majú nepriaznivý vplyv na priľnavosť. Adsorbované častice spôsobujú znižovanie hydrofilicity povrchu. Hydrofilicita, adhezivita a zmáčavosť povrchu sa veľmi dobre posudzujú prostredníctvom merania kontaktného uhlu. V tejto práci je značná pozornosť venovaná práve meraniu statického kontaktného uhlu. [10] Samotné meranie kontaktného uhlu je možné vykonať rôznymi spôsobmi, v tejto práci bol však použitý najvhodnejší prístup, a to metódou „sessile-drop“, teda pokladanej alebo depozitovanej kvapky na meraný povrch. K meraniu bol využitý klasický „sessile-drop goniometer“, teda aparatúra, ktorá pozostávala z nastaviteľného stojanu na vzorky, nad ktorým bol umiestnený zdroj svetla, a objektívu fotoaparátu, ktorý bol prepojený s kamerou zabudovaného smartfónu. Meranie prebiehalo tak, že kvapka s objemom 3L destilovanej superčistej vody bola depozitovaná na povrch substrátu pomocou mikroinjekčnej striekačky. Cieľom tejto práce bolo nielen stanoviť kontaktné uhly a porovnať ich hodnoty medzi rôznymi typmi materiálov navzájom a po upravách tepelného a/lebo chemického charakteru. Vyhodnotené údaje zachycovali zmeny, ku ktorým došlo na povrchoch daných keramických materiálov pri adsorpcii organických molekúl. Proces tepelnej úpravy (kalcinácia na teplote 800°C, následne pokles na teplotu 600°C, po celkovú dobu 16 hodín) bol aplikovaný na všetkých typoch vzoriek, kde niektoré sa medzi sebou líšili teplotou slinovania. Ihneď po kalcinácii boli vzorky podrobené meraniu kontaktných uhlov, z ktorého jasne vyplynulo, že hydrofilicita a zmáčavosť povrchu sa zvýšila. Tento jav bol pozorovaný na všetkých vzorkách, a na všetkých vzorkách sa hodnoty kontaktného uhlu líšili veľmi významne od hodnoty, ktorá bola získaná v tzv. primárnom meraní. Všetky detailné hodnoty a vyhodnotené výsledky sú posudzované v časti diskusia. Ďalšou úpravou povrchu, ktorá bola vykonaná na vybraných vzorkách, bolo čistenie povrchu etanolom. Proces bol opäť realizovaný na všetkých vzorkách. Potom, ako boli zrealizované všetky merania na kalcinovaných vzorkách, boli všetky tieto vzorky ponorené do etanolu na približne 2 hodiny. Po vybratí vzoriek a ich osušení na vzduchu boli uskutočnené ďalšie merania kontaktných uhlov. Výsledky priniesli opäť rozdielne hodnoty v porovnaní s predchádzajúcimi meraniami a sú rozvinuté v časti diskusia.

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