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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.
101

Vzrůstající důležitost energetické a vojenské bezpečnosti Visegrádské skupiny / Growing importance of energy and military security of the Visegrad Group

Kierczak, Natalia January 2013 (has links)
The thesis researches whether in the Visegrad Group there is growing importance and securitization of energy security and military security leading to further cooperation based on recent crises. The thesis also researches whether Russia is perceived as a threat. This is done through content analysis of national security strategies, energy security strategies and military or defence strategies, as well as discourse analysis of official statements presented by ministries and governments of the Visegrad Group states. In the text, also materials published by the Visegrad Group as a whole are analysed. The discourse analysis in case of the states is focused on moments of crises. In energy security field, three crises were chosen: gas crises of 2006 and 2009, as well as oil crisis of 2008. In the chapter about military security, two events were chosen- conflict in Georgia in 2008 and military exercises in 2009. As it is presented, cooperation in energy security is already taking place and cooperation in military affairs in form of battlegroup is planned. Especially in energy security, a link between recent crises, their securitization and cooperation might be seen based on the research.
102

Stanovení hladin mastných kyselin ve vybraných tkáních / The determination of fatty acids level in chosen tissues

Kynclová, Kamila January 2021 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Candidate: Kamila Kynclová Supervisor of Diploma Thesis: Mgr. Monika Kuchařová, Ph.D. Title of Diploma Thesis: Determination of fatty acids levels in selected human tissues Fatty acid are an essential part of many metabolic processes in the body. The theoretical part of the the thesis presents primarily omega-3 and omega-6 fatty acids, their general characteristics, metabolism and their effect on various disease. The roles of fatty acid in cancer, neuropsychiatric and inflammatory diseases are described here. The thesis also mentions the method of gas chromatography, which was used to determine the levels of fatty acids. The experimental part of the thesis includes method, chromatographic analysis and results. 13 fatty acids in 7 different tissues were analyzed: subendocardial tissue, liver parenchymal tissue, kidney and adrenal tissue, skeletal muscle tissue, adipose and brain tissue. Tissues were collected from 20 healthy, suddenly deceased, cadavers. Donors were divided into two groups according to age. The obtained data were statistically processed and divided according to individual fatty acids. In the end the results between the two groups were evaluated with a possible explanation of the...
103

Využití GC/MS při analýze léčiv / The use of GC/MS for the analysis of drugs

Sýkora, Richard January 2011 (has links)
This diploma thesis is based on the current issue of the presence of pharmaceuticals in various components of the environment. Concerning the contamination by residues of pharmaceuticals the most affected environment is the aquatic environment where these substances leaks especially from wastewater treatment plants, which eliminate them during the cleaning process only partially. This work is focused on the selected group of pharmaceuticals, non-steroidal anti-inflammatory drugs (salicylic acid, ibuprofen, caffeine, naproxen, ketoprofen, diclofenac) in waste water. For analysis purposes two types of sampling were used and compared: the conventional spot sampling of wastewater and the sampling using passive samplers POCIS. The sampling took place at the inflow and outflow of the wastewater treatment plant in Brno Modřice. The solid phase extraction (SPE) using Oasis HLB columns was used as the extraction method. Extracted sample was derivatized then. Derivatization agents were: MSTFA (N-methyl-N-(trimethylsilyl)trifluoroacetamid) and BSTFA (N, O-bis(trimethylsilyl) trifluoroacetamid). The final analysis was performed using gas chromatography with mass spectrometric detection Time-of-Flight (GC/TOF-MS).
104

Nové metody používané při zjišťování příčin vzniku požárů / Newe methods used for the finding of fire causes

Přichystal, Lukáš January 2011 (has links)
Master’s thesis deals with a determination problem of ignitable liquids from fire debris. The aim of this work is to introduce the properties of used fire accelerants and to give an overview and evaluation of the various techniques which can be conducive to the fire investigator. Determination of fire accelerants from fire debris was made by the technique of solid phase microextraction (SPME) with subsequent chemical analysis by GC/MS. Based on the chromatographic results were established the target compounds and reconstructed ion chromatograms which are typical for some kinds of flammable liquids. There were used gasoline, diesel, kerosene and technical gasoline (white spirit) as the fire accelerants. This work also deals with the influence of interfering products in fire debris analysis, including their identification and characterization. Different kinds of substrates were burned, extracted and analyzed in order to identify all the interfering products that they may release.
105

Využití plynové chromatografie ke studiu permeace toxických látek bariérovými materiály / The Study of Permeation of Toxic Compounds through Barrier Materials Using Gas Chromatography

Brtníková, Jana January 2009 (has links)
Transport phenomenon of gas and vapors through polymer barrier materials as well as the factors affecting permeability of gaseous and liquid toxic compounds were investigated and results are presented in this thesis. Permeation characteristics investigation methods were elaborated and verified with focusing on utilization of gas chromatographic method and its instrumental modifications.
106

Analýza složení samčího sexuálního feromonu různých populací tropické ovocné mušky Ceratitis capitata (Diptera, Tephritidae) / Analysis of male sex pheromone of different population of tropic fruit fly Ceratitis capitata (Diptera, Tephritidae)

Ježková, Zuzana January 2012 (has links)
The Ceratitis capitata is a very important agricultural pest, whose reproduction behaviour is controled by chemical signals. Males initiate mating by creating leks, where they release sexual pheromones to attract females. The main goal of this diploma thesis was to determine the influence of host plants on the composition of male sex-pheromones C. capitata and to compare emanations of wild males with those originating from laboratory population. We studied the chemical composition of volatiles, released by calling males C. capitata from laboratory and two wild populations, using two-dimensional gas chromatography with time-of-flight mass spectrometric detection (GC×GC-TOFMS), gas chromatography with electroantennographic and flame ionization detection (GC-EAD-FID). All data were statistically analyzed by multivariate data analyses. Significant differences were observed in the quantitative and qualitative composition of the chemical emanations among males from the three populations. The GC-EAD-FID analyses revealed fourteen antenally active compounds with a possible behavioral function. Isomenthone, geraniol, bornyl acetate, geranyl acetone and ethyl octanoate were newly identified antenally active compounds of C. capitata male sex pheromone. Statistical analyses indicated that males and females of...
107

Využití plynové chromatografie s hmotnostně spektrometrickou detekcí pro posouzení kontaminace odpadních a povrchových vod rezidui léčiv / Application of Gas Chromatography with Mass Spectrometric Detection for the Assessment of Drug-residue Contamination of Wastewaters and Surface Waters

Lacina, Petr January 2012 (has links)
This work is based on the current issue of increasing concentrations of pharmaceutical residues in various components of the environment. These new environmental contaminants continuously enter the environment. The most affected environmental component is the aquatic environment. This study is focused on the development and optimization of reliable analytical method, which can determine selected drugs in the aquatic environment (waste waters and surface waters) qualitatively and quantitatively. The target compounds were selected mainly from the group of non-steroidal anti-inflammatory drugs (NSAID): salicylic acid, acetylsalicylic acid, clofibric acid, ibuprofen, acetaminophen, caffeine, naproxen, mefenamic acid, ketoprofen and diclofenac. NSAIDs are one of the most used drugs in Czech Republic. For the final analysis of this study was used the comprehensive two-dimensional gas chromatography with mass spectrometric detection Time-of-Flight (GCxGC-TOF MS). It is a very sensitive and reliable analytical method for trace and ultra-trace analysis. Simultaneously, solid phase extraction (SPE) and derivatization are optimized in this work. Optimized analytical method including SPE, derivatization with MSTFA (N-methyl-N-(trimethylsilyl) trifluoroacetamide) and final analysis by GCxGC-TOF MS were applied successfully for the analysis of real samples. Samples of waste water were collected from the waste water treatment plant in Brno – Modřice and samples of surface water were collected from two river streams Svratka and Svitava in Moravian region. The range of concentrations of selected drug residues varied from one to tens of g/L in wastewater and from tens to hundreds of ng/L in surface waters. The degree of wastewater and surface waters contamination by drug residues is assessed in conclusions of the work. Simultaneously, spontaneous degradation of selected drugs in water and removal efficiency of the wastewater treatment plant is assessed in conclusions of the work. The developed method is usable for monitoring and environmental analysis of water ecosystems. It is usable not only for selected drugs, but even for other organic compounds with similar properties.
108

Vývoj společné energetické politiky EU v kontextu spolupráce mezi EU a Ruskem / Emergence of the Common Energy Policy of the EU in the context of EU-Russia Energy Cooperation

Radová, Ivana January 2013 (has links)
This master thesis The emergence of the Common energy policy of the EU in the context of the EU-Russia energy cooperation aims to answer the question of whether Russia with its aggressive energy policy (gas crisis, gas pipeline projects) stands behind the EU's inability to advance a strong Common energy policy despite all its efforts. By analysing the member states' behaviour in relation to the key development in the energy field, we will be able to assess Russia's influence. The thesis will then demonstrate that it is the divergent national policies of the member states that stand behind the EU's inability to push forward a Common energy policy. The member states, in the pursuit of the maximization of benefits, support the Common energy policy only if it aligns with their national interests. The categorization of the member states based on their dependence on Russian gas and the size of their gas markets in relation to Russian gas exports will provide broadly representative conclusions about the member states behaviour towards the Common energy policy based on these two variables.
109

Technicko-ekonomické hodnocení systému pro využití odpadního tepla z plynové mikroturbíny / Technical and economic evaluation of the gas microturbine with the waste heat recovery system

Slovák, Rostislav January 2018 (has links)
The use of gas microturbines as a primary unit in CHP is still weak in the industrial process. It gives the driving force to the main aim of this master thesis, which is the technical and economic evaluation of the gas microturbines waste heat recovery system, which is the key factor for their economic sustainability. Assignment contains description of CHP system that was gradually built in LENP laboratory, part of NETME Centre. The author has joined the final work before start-up of the CHP system. He presents and describes results of the first experiments on this unit. The flue gas of a microturbine was used for heating water by heat exchanger flue gas–water and for direct linen drying. The case study of laundry with capacity 10 tons per shift was developed in cooperation with companies in laundry care. Results of those tests were used to process integration and utilization of this professional industrial laundry All obstacles found and opportunities of the use of microturbines are comprehensively described and tested in case studies, which are simulated in Chemstation Chemcad Software. Results of the thesis are expected to be useful these fields: the use of gas microturbines in industry & energy savings in industrial laundries.
110

Experimentální ověření kogeneračního systému na bázi plynové mikroturbíny / Experimental verification of a gas micro-turbine cogeneration system

Buřil, Lukáš January 2019 (has links)
This master’s thesis deals with problematics of natural gas microturbine integration into industrial laundry operation. This integration means utilization of waste heat for direct drying and water heating in a heat exchanger. This heated water can be used in further laundry processes, for example laundering. All the experiments were carried out on the cogeneration system that is installed in Laboratory of Energy Intensive Processes in NETME Centre at the Faculty of Mechanical Engineering of Brno University of Technology. This system consists of a natural gas microturbine Capstone C30 with nominal electric power of 30 kW, an industrial dryer Primus DX55 with a nominal capacity of 55 kg for laundry and a heat exchanger Vakading type Vakavlas with nominal power of 53 kW. All necessary theoretical and technical preparation was done in order to carry out experiments as follows: • Standard drying program • Water accumulation test • Test of performance of heat exchanger • Direct drying with the use of microturbine’s flue gases These experiments were analyzed and discussed within this thesis. The main contribution of this work is as follows: • Summary of all the knowledge in the area of direct drying • Creation of methodology of utilization of flue gases for direct drying not only in laundry industry but in related fields • Summary of requirements and ways of heat exchanger testing and determination of heat exchanger parameters • Determination of optimal working settings of installed cogeneration system • Description of weak spots in the system and suggested improvements • Basic economic analysis of operating costs During the experiments, it was found that in case of direct drying better results could be achieved in comparison with standard drying. The functionality of the whole system together with the heat exchanger was verified and thus also the possibility of integrating the turbine into the washing process was confirmed. The integration of a natural gas microturbine is both technically and economically feasible for many industrial applications.

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