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Differences in CO2 Extraction of Vegetable Oils, Essential Oils, and Minor Components from Plants
Sovová, Helena
Significant progress in understanding the phenomena that control supercritical fluid extraction from plants was made in the last years and is reflected in the literature. Combination of chemical engineering approach and botanical knowledge has appeared to be fruitful for the choice of extraction model and even for the prediction of extraction kinetics. This contribution refers to the papers utilizing knowledge of plant microstructure and location of extracted substances together with extraction equilibrium and attempts to specify the differences among extraction kinetics of vegetable oils, essential oils, and other substances. The most abundant substances like vegetable oils in seeds can be regarded in first approximation as non-interacting with plant matrix, in contrast to the minor components whose equilibrium concentration in CO2 is affected by their adsorption on matrix and often also by co-extracted substances.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_C22012102414100 - PDF
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The natural seasonal changes in the food choice and digestive tract of wild ruminants
Kamler, Jiří ; Homolka, Miloslav
Herbivore populations all over Europe have been strongly influenced by human activities. A combination of harvest, changes in forest structure, supplementary feeding, predator extirpation and others factors have led in most cases to increases of their populations and a severe impact on the composition and structure of the forest vegetation. The food choice of free living ungulate species is strongly influenced by season and animal species and changes in diet composition and quality cause the changes in the digestive tract. Effective management of ungulate populations and forest ecosystems should be based not only on detailed information about the impact of deer browsing and the number of deer to harvest but also on the density of deer species, the food supply, the structure of diets consumed by individual species, attraction and quality of the individual components of food supply the total quality of food taken and seasonal changes in digestive tract.
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Interaction between TiAl melt and coated oxide refractories
Dočekalová, Kateřina ; Dlouhý, Antonín ; Zemčík, L. ; Fiala, J.
The present study focuses on reactions between ceramic crucibles and molten TiAl intermetallics. Coating strategies are investigated that exhibit a potential in slowing down the decomposition of the crucible wall. Uncoated crucibles (system TiAl melt - Al2O3 crucible) and crucibles with the coat (system TiAl melt - CaO coat - Al2O3 crucible) were used in melting and casting experiments. The reference state of the coated crucible before the melting trial was also investigated. Results of the SEM, EDAX and X-ray diffraction analysis contributed to the identification of the reaction zone and its chemical composition. The melt contamination with oxide inclusions results from the erosion process in which individual components of the melt diffuse along grain boundaries of the refractory and activate chemical reactions that decompose the crucible wall. Assessment of thermodynamic parameters associated with the chemical reactions helped in identifying the nature of the erosion process.
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Design of hydrogen pressure tank installation on the VUT 001 Marabu wing
Koštial, Rostislav ; Juračka, Jaroslav (referee) ; Píštěk, Antonín (advisor)
The content of this Master thesis to design installation of hydrogen pressure tanks for airplane VUT RAY 051. Survey was conducted of the available fuel cell on the market. Position of the tank was chosen over the wing using components for mounting a jet engine TJ100 M for aircraft VUT 001 MARABU. For fuel tanks were designed fairings. Further was calculated mass and centre of gravity analysis of aircraft, basic flight performance of aircraft and the drag variation in the location of the tanks above the wing. Further the strain and strength of hinges was calculated.
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Additional Load Elimination at Suspension Components Testing
Brychta, Tomáš ; Porteš, Petr (referee) ; Ramík, Pavel (advisor)
The thesis first provides a survey of acceleration tests with the focus on automotive component testing. The survey covers multiple types of acceleration tests and sources of stress. The thesis then includes a MATLAB application for the removal of inertia forces, which is applied on two shaft configuration models developed in Pro Engineer. Both models are subjected to stress analysis using FEM in Ansys. The thesis has been carried out in collaboration with TRW-DAS Dačice.
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Study of the synthesis and structure of ceramic perovskite materials for energy applications
Strejček, Josef ; Bartoníčková, Eva (referee) ; Cihlář, Jaroslav (advisor)
Method, so called “glycin- nitrate process”, combined with high temperature solid state reaction, of preparation multi- component ceramic perovskite materials was studied. Two types of perovskite systems were prepared by this method. Firs one, based on LaNiO3 doped by calcium and aluminium and second one, based on SmFeO3 doped by calcium and nickel or cobalt. This method made possible preparation of one phase perovskite or perovskites with few percent of nickel in form of oxide. In systems containing both nickel and calcium another phases rich in calcium and nickel appeared.
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Propagation of inclined cracks to the interface of ceramic laminates
Novotná, Lenka ; Trunec, Martin (referee) ; Chlup, Zdeněk (advisor)
Composite materials with laminated structure provide advantages which are utilised during component design. Low density, temperature and chemical stability are the profitable properties predetermining application of ceramic laminates. The main obstacle for wide spread of ceramic materials is their inherent brittleness. Therefore, in this thesis, the crack propagation in ceramics laminates has been extensively studied. Laminated structures with various volume fractions of components (alumina and zirconia) were prepared by electrophoretic deposition. Evaluation of crack propagation through the interface and determination of basic mechanical properties was conducted on the basis of extensive literature search. Crack deflection originated in both presence of internal stresses and differences in elastic modulus during the crack interface passing was monitored. A special type of specimen geometry was employed with the aim to set arbitrary angle between crack and interface. It was experimentally found that the degree of crack deflection is dependent on entering angle and volume fraction of components. Higher crack deflection was already found in the bulk of the test piece comparing to the test piece surface. The 3D fracture surface reconstruction generated using laser confocal microscopy was used in this detailed crack propagation study. Further basic elastic and strength characteristics of laminates were determined and compared to those obtained from monolithic materials. The validity of the mix rule for elastic characteristics was confirmed by comparing of elastics modulus. The most reliable method for elastic modulus determination was marked the dynamic resonance method due to low scatter and consistency in measurement. The flexural strength of all laminates tends to be close to the flexural strength of the weakest component. Therefore the mix rule is not applicable for flexural strength estimation on the contrary of elastic characteristics. The change of component volume fraction leads only to change of flexural strength scatter. Thanks to gained knowledge about crack propagation and basic characteristic determination will be possible to design ceramic laminates more efficiently for given needs of application.
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Extending Java PathFinder with Behavior Protocols
Plšek, Aleš ; Kofroň, Jan (referee) ; Adámek, Jiří (advisor)
The Component-based programming is an aproach to efficient development of software applications, where Behavior protocol is a formalism used for behavior specification of components. To further ease the development of a component application, System Correctness analysis is employed to discover errors at the designe time. However, without verifying that a component implementation complies with its behavior protocol, the analysis of the system could be based on unsatisfied property. This thesis addresses the problem of verification that a component implementation adheres to its behavior protocol. By employing Java PathFinder Model Checker it offers an ambitious solution which is successfully addressing one of the issues of the software component development.
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Intercultural communication - sociocultural skills of students of Russian and English language at secondary schools
Poláčková, Vladimíra ; Žofková, Hana (advisor) ; Hlaváček, Antonín (referee)
The diploma thesis deals with problems of intercultural commnunication, especially with its role in foreign language teaching (chiefly Russian and English language). It introduces the term commnunicative skill as the fundamental goal of contemporary foreign language didactics because it represents the key skill which students of foreign language should acquire. In the first place it is focused on sociocultural skill which represents partial component of communicative skill. The practical part of the thesis is based on via questionaire survey and presents stereotypes and prejudice of students at secondary schools about nationalities whose languages they study. It also presents a probe in students' knowledge of sociocultural customs in countries whose languages they study. Powered by TCPDF (www.tcpdf.org)
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Stress-strain analysis of lower limb prosthetic
Musilová, Kateřina ; Fuis, Vladimír (referee) ; Návrat, Tomáš (advisor)
This master thesis deals with lower-limb prosthesis. The aim of the first part of this work is stress-strain analysis of trans-tibial prosthesis, which is understand without prosthetic socket and the foam prosthetic feet. Analysis is made using finite element method in ANSYS Workbench 12.0 software. For the purpose of setting up the computational model it is necessary to make few partial models. Model of geometry of the prosthesis is made in SolidWorks 2009. Based on the outputs of stress-strain analysis and the results evaluation, the critical component is chosen and this one is evaluated according to limite state for fatigue. The algorithm of evaluation of named component in the state of high cycle fatigue is discussed in the second part of this thesis.
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