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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

Konformace a molekulární organizace huminových kyselin ve vodných roztocích / Conformation and molecular organization of humic acids in aqueous solutions

Věžníková, Kateřina January 2012 (has links)
This diploma thesis deals with the conformation and molecular organization of humic acids in aqueous solutions. Humic substances have heterogeneous and polydisperse nature, therefore their secondary chemical structure has not yet been defined properly, neither has their conformational arrangement. The conformation of humic substances in the solutions is mainly stabilized by weak disperse forces, such as Van der Waals, -, CH- interactions and hydrogen bonds. Humic substances in the solutions tend to form aggregates that are held together mostly by the intermolecular hydrophobic interactions. Concentration series of humic acids were prepared in three different mediums of constant ionic strength: NaOH and NaCl (prepared either by neutralization NaOH by HCl or direct dilution by solution of NaCl). Several analytical methods have been used to determine conformation and molecular organization of humic acids: potentiometric determination of pH, direct conductometry, ultraviolet and visible spectroscopy, density measurement, dynamic light scattering, laser Doppler velocimetry and high resolution ultrasound spectrometry. It was confirmed that the conformation and molecular organization of humic acids in aqueous solutions depend not only on pH of medium, but they also depend on chemical nature and concentration with the same pH. Results showed that hydrodynamic diameter of particles is significantly increasing in NaCl medium prepared by neutralization NaOH by HCl, particularly at low concentrations, which corresponds to higher values of zeta potential obtained. Concentration dependencies of ultrasonic velocity and compressibility also indicate the changes in conformation and molecular organization corresponding with results from other methods used.
92

Testování možností enkapsulace vybraných druhů makromolekul a bakterií / Possibilities of encapsulation of particular types of macromolecules and bacteria

Kapar, Jiří January 2013 (has links)
Presented diploma thesis is focused on testing encapsulation methods of enzymes and probiotic bacteria. In the theoretical part a summary of different encapsulation techniques used in food industry is given. Further, materials for encapsulation, above all polysaccharides are presented. Next, some procedures of encapsulation of biopolymers and microorganisms – mainly enzymes and probiotic cultures are discussed. In the experimental part methods for preparation of several types of particles based on polysaccharides and liposomes are introduced. Particles were used for encapsulation of selected hydrolytic enzymes and probiotic strains Bifidobacterium breve a Lactobacillus acidophilus. The encapsulation effectiveness was evaluated by analysis of total proteins and enzyme activities. Particles sizes and their stability in water, in selected model foods and model body fluids were observed, too. According to results obtained in this work it was found that encapsulation of enzymes into polysaccharide particles were succesfull in all types of particles (encapsulation effectivness was more than 50 %). Polysaccharide particles showed a very good stability in body fluids as well as in model foods. As the most suitable materials for enzymes encapsulation chitosan and liposomes were found. Polysaccharide particles were used also for the encapsulation of microorganisms. The stability of particles with lactic acid bacteria was similar to particles containig enzymes, very good stability was verified aslo in model foods and model body fluids. Encapsulation enables long-term stabilization of biologically active compounds as well as posibility of their transport and controlled releasing in gastrointestinal tract. Encapsulation of probiotic bacteria could preserve their viability and long-term survival until the product expiration date. Thus, encapsulation is one of the most promissing procedures for production of foods and food suplements of great quality and high additional value.
93

Tone-mapping pro HDR obrazy / Tone-Mapping HDR Images

Nejezchleb, Ivan Unknown Date (has links)
This thesis focuses on the high dynamic range (HDR) imaging problematic. It describes process of capturing and storage of HDR images in brief. Main part of thesis deals with techniques of how to display HDR images on common visual display devices, which are not able to represent them directly. This process is called tone-mapping. It is firstly described in general and than the text focuses on several techniques of tone-mapping, mainly on tone-mapping using bilateral filtering.
94

Tone-mapping HDR obrazů / HDR Tone-Mapping

Vančura, Jan January 2010 (has links)
This thesis concerns with the introduction to the problematics of images with high dynamic range (HDR) and possibilities of HDR images compression options for display on devices with a low dynamic range (LDR). In the introduction is described historical evolution of recording of reality. It is focusing towards point of view of physics, human visual perception and digital recording. There are described the ways of generating and holding of HDR images. The thesis is corncerned to the techniques of HDR compression, it means the tone-mapping. The different techniques of tone-mapping are explained and specific aproach is targeted to the gradient domain high dynamic range compresion.
95

Dynamický Loewensteinský ergoterapeutický kognitivní test u osob se získaným poškozením mozku v produktivním věku / Dynamic Loewenstein occupational therapy cognitive assessment in individuals after obtaining brain injury in working age

Křelinová, Michaela January 2016 (has links)
The thesis Dynamic Loewenstein occupational therapy cognitive assessment in individuals after obtaining brain injury in working age deals with a comparison of the level of the brain injured and non-brain injured people's cognitive functions with the aid of the Loewenstein Occupational Therapy Cognitive Assessment battery (DLOTCA). The theoretical part is focused on an issue of the acquired brain injury, a description of cognitive areas and as well their pathology due to this injury. The aim of the practical part is to test the cognitive functions with the aid of the Loewenstein Occupational Therapy Cognitive Assessment. The survey's main object is the applicability of the working version of the Loewenstein Occupational Therapy Cognitive Assessment battery (DLOTCA), its translated version. The testing was carried out on seventy probands devided into three groups. Healthy people (n=50), cerebrovascular accident patients (n=10) and traumatic brain injury patients (n=10). Test results confirm all the stated hypothesis because it did not meet the prerequisites of the total evaluation. We assumed that a person healthy population will reach 100% success rate testing, which some individuals reached. In the assessment of persons with stroke by 6 out of 10 tested achieved a lower evaluation scores in most...
96

Valuation and Hedging of Foreign Exchange Barrier Options / Ocenění a zajíštění měnových bariérových opcí

Mertlík, Jakub January 2004 (has links)
The main aim of this thesis is in analyzing and empirically testing the various valuation models and hedging schemes of foreign exchange barrier options and their robustness with respect to changing of market conditions. The purpose of the main empirical section is to get a detailed understanding of the static and dynamic performance of the analyzed models for the barrier options payoff mainly in the extreme market conditions, where we performed a benchmarking of the various hedging schemes. As a by-product, we analyzed the accomplishment of some of the model assumptions in real world setting, and the model dependency of the barrier options.
97

Aplikace Balanced Scorecard v bankovní instituci / Application of Balanced Scorecard in a banking institution

Nechanický, Jakub January 2013 (has links)
This thesis focuses on the use and application of strategic tool Balanced Scorecard (BSC) for managing banking institution and translation the strategy into particular objectives and initiatives. Theoretical background affects both BSC framework taking into account modern trends of the dynamic system conception and also basics of information society, strategic considerations and system dynamics theory in relation to creating and application of the BSC in the organization. The practical part provides an introduction to the issues of examined institution, the current state of sharing strategic objectives, fundamental analysis to detect key features of the organization and the market and especially BSC formation. There is an analysis of the BSC system in details, translation strategy into concrete objectives, targets, initiatives and also selected measures. The integrity of the thesis is supplemented by a suggested process of dynamic BSC implementation to the institution, introduction of the tool for building a dynamic model for simulation of strategies and the concept of the user interface in the selected tool for sharing BSC through the whole organization.
98

Biosurfaktanty a jejich využití pro inkorporaci hydrofobních domén do moderních nosičových systémů / Utilization of biosurfactants for incorporation of hydrophobic domains into modern controlled-release systems

Nešpor, Tomáš January 2021 (has links)
This work deals with the current topic of carrier systems. Since the biggest problem is the passage of hydrophobic drugs through the bloodstream, or through universal body barriers (eg blood-brain), it is necessary to chemically modify these carriers in order to be able to administer hydrophobic substances effectively. Based on a literature search, several systems are designed and subsequently studied, in which there is a presumption of possible use for carrier systems and at the same time they have biosurfactants incorporated in them due to their ability to solubilize hydrophobic molecules. The theoretical part of this work will describe the individual biosurfactants, the process of their production, their physicochemical properties, and the possibility of their use in carrier systems. At the same time, the individual carrier systems, the procedure of their preparation, the possibilities of their use are described, and their advantages and disadvantages are also compared. In the practical part, the screening of both individual substances and their mutual interactions, as well as methods used to study the emerging structures is then performed. The study of molecular interactions is primarily performed using the technique of dynamic light scattering. The next part describes the optimization of hydrogel formation with incorporated biosurfactants in their structure and then the formed gels are subjected to rheological and solubilization tests. The study of the internal structure of these gels is performed using a scanning electron microscope.
99

Studium interakcí tenzidové složky přípravku Septonex s vybranými proteiny / Study of interactions of the surfactant component of Septonex with selected proteins

Bohunská, Miroslava January 2021 (has links)
The study of protein and surfactant interactions is of great significance in a number of applications, such as the cosmetic, food or pharmaceutical industries and many others. However, they require further study due to their compositional complexity and the limitations of current analytical approaches. In this thesis, the cationic surfactant septonex in combination with two differently charged proteins lysozyme and bovine serum albumin under different physiological conditions (temperature, surfactant concentration, environment and others) was selected to study the interactions. Characterization of protein-surfactant interactions is a very important but challenging task, therefore it is essential to use appropriate approaches to explore the nature of these interactions. In order to unify the information to provide rational models, calorimetric methods (DSC, ITC) and dynamic light scattering were used. Isothermal titration calorimetry monitors the evidence for the formation of the system of the mentioned substances and information on aggregation behavior, differential scanning calorimetry characterizes the thermal stability of proteins and dynamic light scattering made it possible to monitor changes in particle size. Both proteins have been proven to interact with positive septonex, even if the lysozyme molecule is also positively charged. However, significant differences were found between the two proteins. From the obtained results it is evident that the identical charge of the protein with the surfactant has an effect on the intensity of the measurement, although all measured interactions showed an endothermic character.
100

Silikonový tlumič torzních kmitů šestiválcového vznětového motoru / Silicone torsional vibration damper for a six-cylinder diesel engine

Kovář, Lukáš January 2017 (has links)
The aim of this thesis is to design crankshaft for in-line six-cylinder diesel engine and to design viscous torsional vibration damper for the cranktrain of specified parameters. The thesis includes the creation of a dynamic torsional model of cranktrain and calculation of forced vibrations of mechanism with and without damper. Part of this thesis is also strength analysis of the designed crankshaft with damper using the Finite Element Method (FEM).

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