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Supercritical Fractionation of Volatiles and Non-volatiles from Different Plant Sources
Topiař, Martin
The focus of this work was on using the SFE combined with different fractionation techniques (additional separator, sorption on silica gel in one step with the extraction) in a range of pressures and temperatures (9–30 MPa, 40–50 °C) to enhance volatiles in extracts from the leaves of eucalyptus. Its essential oil is widely used in cough pills or toothpastes and in addition, several studies proved insecticidal and repellent activity of eucalyptus extract.1,2 The efficiency of SFE in terms of extract composition and yield was compared with hydrodistillation. The composition of volatiles in the isolates was determined using GC-MS and GC-FID.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_C22015061709330 - PDF
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Unconvential monetary policy adopted by ECB and FED in 2008-2015
Pörner, Marek ; Šetková, Lenka (advisor) ; Ševčíková, Michaela (referee)
The main aim of this thesis is to analyse the accomplishment of the goals set, namely those of the selected unconventional monetary policies approved by the Federal Reserve System and the European Central Bank in response to the last financial crisis. With the FED the attention is focused on Quantitative Easing, whereas with the ECB it is focused on the programmes called Enhanced Credit Support, SMP, OMT and EAPP. Important parts of this thesis are also the explanation of the transmission mechanism of the unconventional monetary policy, the evaluation of macroeconomic impacts of these non-standard tools, the comparison of procedures of the two monitored central banks, but mainly the analysis of selected risks related to those tools. The principal method was an empirical analysis supported by economic studies dealing with the issues mentioned above. In the thesis it was discovered that the individual goals of the monitored programmes were achieved (with the exception of the SMP). With the programme EAPP no conlusion can be drawn because the programme has not been finished yet. Nevertheless, these non-standard tools bring certain risks such as a creation of a bubble in the markets of assets, a redistribution of wealth, a spillover effect, etc. For that reason it will be possible to evaluate the overall effect of the unconventional monetary policies only after a longer time period.
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Speculation on oil markets and its impact on commodity's price
Melcher, Ota ; Taušer, Josef (advisor) ; Baláž, Peter (referee) ; Müller, Štěpán (referee)
This study aims to analyse the precrisis period on the oil markets with a primary objective of assessing the role of speculation in the commodity's price development and its volatility. First it depicts the rapidly increasing speculative activity on the futures market together with the parallel oil price surge. The speculation is initially proxied by non-commercial traders' positions and subsequently quantified by Working's T-index. The paper then uses speculative traders' positions and both spot and futures prices to test for Granger causality within the framework of VAR models. For the sake of consistency it also evaluates causal links between speculation and inventories level. Further the study investigates the speculation impact on volatility of oil prices by employing various approaches in volatility quantification including GARCH models. Contrary to expectations we find that the speculatio's impact on both prices and their volatility is rather insignificant. In the last chapter we therefore seek for an explanation of the oil price developments by examining the market fundamentals. The interaction of supply and demand finally gives substantial evidence for understanding the price developments in the precrisis period.
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Analysis of the marketing activities in nonprofit organization INEX-SDA
Müllerová, Michaela ; Procházková, Markéta (advisor) ; Polcar, Jakub (referee)
The aim of this thesis is to analyze marketing activities of nonprofit organization INEX-SDA and make recommendations relating to the marketing mix which would increase awareness of this foundation and also increase voluntary help from the public. The thesis is divided into two parts. First part deals with theoretical definition of marketing and its specifics related to the nonprofit sector. The theoretical part is followed by a practical part in which organization INEX-SDA and the individual elements of the marketing mix are specified. In this part there was also done marketing research. With the analysis of marketing activities information is obtained which together with the theoretical knowledge leads to recommendations relating to the marketing activities of this non-profit organization. The thesis ends with an overall summary.
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STRAIN ENGINEERING OF THE ELECTRONIC STRUCTURE OF 2D MATERIALS
del Corro, Elena ; Peňa-Alvarez, M. ; Morales-García, A. ; Bouša, Milan ; Řáhová, Jaroslava ; Kavan, Ladislav ; Kalbáč, Martin ; Frank, Otakar
The research on graphene has attracted much attention since its first successful preparation in 2004. It possesses many unique properties, such as an extreme stiffness and strength, high electron mobility, ballistic transport even at room temperature, superior thermal conductivity and many others. The affection for graphene was followed swiftly by a keen interest in other two dimensional materials like transition metal dichalcogenides. As has been predicted and in part proven experimentally, the electronic properties of these materials can be modified by various means. The most common ones include covalent or non-covalent chemistry, electrochemical, gate or atomic doping, or quantum confinement. None of these methods has proven universal enough in terms of the devices' characteristics or scalability. However, another approach is known mechanical strain/stress, but experiments in that direction are scarce, in spite of their high promises.\nThe primary challenge consists in the understanding of the mechanical properties of 2D materials and in the ability to quantify the lattice deformation. Several techniques can be then used to apply strain to the specimens and thus to induce changes in their electronic structure. We will review their basic concepts and some of the examples so far documented experimentally and/or theoretically.
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Alternative methods of leading childbirth
PAPAI, Daria Kristina
The topic of my bachelor thesis is "Alternative methods of child delivery". The theoretical part describes the physiological delivery its particular phases and their progression. In addition, I aim to explain what the term alternative birth means, and what it includes. The various alternative positions are described, which can be used to facilitate childbirth, as well as their appropriate use during the particular delivery phases. The theoretical part is concluded by descriptions of pain relief methods, including the description of both pharmacological and non-pharmacological methods. The second part of the thesis is a practical part, summarizes the results of an evaluation research. The aim was to explore the most used alternative methods and to identify the views and experiences of women with alternative methods and aids used during delivery in selected hospitals. Furthermore, the aim was to describe the regions of the Czech Republic in terms of the use of alternative aids and procedures. The hypotheses were formulated based on previous experiences and personal opinions of the author of the thesis. The research sample consisted of women after a spontaneous child delivery in the České Budějovice Hospital and in the Znojmo Hospital. The research was conducted in the form of an anonymous questionnaire survey, using a non-standardized questionnaires. The results of the survey were compiled in tables and the chi-square test was applied as a method for statistical processing and verifying the hypotheses.
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Effect of snowpack on runoff generation during rain on snow event.
Juras, Roman ; Máca, Petr (advisor) ; Ladislav , Ladislav (referee)
During a winter season, when snow covers the watershed, the frequency of rain-on-snow (ROS) events is still raising. ROS can cause severe natural hazards like floods or wet avalanches. Prediction of ROS effects is linked to better understanding of snowpack runoff dynamics and its composition. Deploying rainfall simulation together with hydrological tracers was tested as a convenient tool for this purpose. Overall 18 sprinkling experiments were conducted on snow featuring different initial conditions in mountainous regions over middle and western Europe.
Dye tracer brilliant blue (FCF) was used for flow regime determination, because it enables to visualise preferential paths and layers interface. Snowpack runoff composition was assessed by hydrograph separation method, which provided appropriate results with acceptable uncertainty. It was not possible to use concurrently these two techniques because of technical reasons, however it would extend our gained knowledge. Snowmelt water amount in the snowpack runoff was estimated by energy balance (EB) equation, which is very efficient but quality inputs demanding. This was also the reason, why EB was deployed within only single experiment.
Timing of snowpack runoff onset decrease mainly with the rain intensity. Initial snowpack properties like bulk density or wetness are less important for time of runoff generation compared to the rain intensity. On the other het when same rain intensity was applied, non-ripe snowpack featuring less bulk density created runoff faster than the ripe snowpack featuring higher bulk density. Snowpack runoff magnitude mainly depends on the snowpack initial saturation. Ripe snowpack with higher saturation enabled to generate higher cumulative runoff where contributed by max 50 %. In contrary, rainwater travelled through the non-ripe snowpack relatively fast and contributed runoff by approx. 80 %.
Runoff prediction was tested by deploying Richards equation included in SNOWPACK model. The model was modified using a dual-domain approach to better simulate snowpack runoff under preferential flow conditions. Presented approach demonstrated an improvement in all simulated aspects compared to the more traditional method when only matrix flow is considered.
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Design of Experiment for Non-Stationary Processes of Production
Jadrná, Monika ; Macák, Tomáš (advisor)
The doctoral thesis is concerned with the services sector and the area of mass production. Particularly, the optimization of the product portfolio of the travel agency and the optimization of production rounds of ammunition.
The theoretical part deals with the current overview of discussed topic. Further, the terminology and methods of the decision-making process are defined to support decision making. The theoretical basis of research focused on the choice of appropriate input variables in the area of services, and on the choice of a particular material option in the production area and appropriate equipment for the production. The theoretical part forms the basis for the practical part of the thesis.
For the doctoral thesis was chosen an enterprise operating in the defined sector. Product portfolio for the services sector is optimised using Fuzzy logic and Fuzzy sets so that the enterprise can maintain its competitiveness in todays highly ambitious market. Product portfolio for manufacture is optimised for achieving desired properties of the product.
The main aim of the thesis is to propose a new methodological approach for the management of selected business processes in their nonstationary time course. The aim of the practical implementation is to verify the functionality of the proposed methodological approach, both in the area of services and in the field of mass production.
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