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ELIMINATION OF NEGATIVE PROPERTIES OF CONCRETE INDUCED BY THE USE OF RECYCLED AGGREGATES USING BASALT FIBERS
Fittl, David ; Nováková, Iveta (referee) ; Bodnárová, Lenka (advisor)
The thesis summarises information about recycled aggregates and basalt fibres, their interaction in composite material such as concrete. It focuses on the potential deficiencies and properties of concrete due to the use of recycled aggregates and on the possibilities of their subsequent elimination of their negative impact by the use of basalt fibres. It characterizes individual raw materials and their interaction in concrete. It includes verification of the properties of the individual sub-components and the resulting concrete itself. An assessment is made of the impact of the use of recycled aggregates on the properties of concrete (compresive strength, static modulus of elasticity, residual flexure tensile strength and others). The thesis discusses the question of whether the same or similar mechanical properties of concrete can be achieved with natural and recycled aggregates using basalt reinforcing fibres. The work provides for the possibility of settlement the values of these concrete parameters by using basalt fibres as a dispersed reinforcement in concrete. The recycled aggregates come from concrete company JARO AS in the north of Norway, where this work was conducted with the financial support from Erasmus+ at The Arctic University of Norway - campus Narvik.
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Study of thermal insulation properties of cement concrete exposed to high temperature
Nováková, Iveta ; Sitek,, Libor (referee) ; Bodnárová, Lenka (advisor)
Master`s thesis is divided in to two parts, practical and theoretical. In theoretical part are listed basic information’s about light weight concrete, special emphasis are given to characteristic and practical application of compact light weight concrete with Liapor aggregates. In this study is described influence of high temperature on concrete structure and chemical, mechanical and physical changes, which take place during exposal to high temperatures. Further is evaluated surface permeability of concrete and addition of polypropylene fibres to concretes resistive to high temperatures. The practical part deals with design, production and testing of cement based concrete with use of different aggregates (light weight aggregates Liapor, basalt). The properties and use for applications in high temperatures is also mentioned. The influence of high temperature on strength, absorption, thermal conductivity, changes of surface permeability and degradation of testing specimens due to heat loads according to normative heat curve (ISO 834). For better transparency are experimental tests divided in to five phases and the measured values are evaluated on the end of each phase. In conclusion are resumed all knowledge’s obtained by testing and evaluated the most suitable formulation. The approach for further research is also mentioned.
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Possibilities of using recycled concrete as fine aggregate replacement in cement screeds
Nováková, Iveta ; Brožovský,, jiří (referee) ; Hubáček, Adam (advisor)
The bachelor thesis deals with summary of knowledge about cement-based screed with partial replacement of natural aggregates by recycled aggregates. Special emphasis is given to describing and studying characteristics of cement-based flowscreed. In this study are described feedstocks with requirements which they must meet and test methods for testing properties of screeds. One part is also given to practical application of cement-based flowscreed with partial replacement of natural aggregates by recycled aggregates.
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BEHAVIOUR OF CEMENTITIOUS COMPOSITES EXPOSED TO HIGH TEMPERATURES
Nováková, Iveta ; Chobola, Zdeněk (referee) ; Sitek,, Libor (referee) ; Wallevik, Ólafur Haralds (referee) ; Pimienta, Pierre (referee) ; Bodnárová, Lenka (advisor)
Fire resistance is becoming increasingly important along with the development of new concrete types with high strength and dense structure with reduced porosity. Such concrete types are susceptible to fire spalling and extensive crack formation. At the moment, there are a limited number of methods for enhancement of fire resistance of existing structures, which could be applied in underground structures with restricted space and limited air exchange, such as tunnels, underground garages or nuclear powerplants. This work is focused on the development of two methods, and both are dealing with porous structure modification. The first method is intentional heat treatment (IHT) method, suitable for the enhancement of fire resistance of existing structures. The second method emphasized the design of air-entrained concrete (AeA-FiResCrete) with the use of “new generation” air-entraining agents suitable for enhancement of fire resistance of newly designed concrete. Testing of compressive strength, porous structure modification was completed by the analysis of “moisture clog,” which contributes to explosive spalling and extensive cracking. The efficiency of developing methods was verified during large-scale testing according to modified ISO834 (m-ISO) curve. No extensive crack formation or explosive spalling was observed during the exposure period during the large-scale testing of slabs with the applied IHT method. The total thickness of the IHT method with configuration IHT200/2, composed of IHT zone and IHT transition zone, penetrated to the depth of 25,5 to 43,0 mm depending upon various concrete types. Moisture clog in AeA-FiResCrete was more significant than in the case of slabs with applied IHT method, and it could be concluded that the IHT method enhances fire resistance of concrete exposed to elevated temperatures without influencing its compressive strength and durability. Results from AeA-FiResCrete testing showed only a slight improvement of its fire resistance.
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TRANSPORT OF NSAIDs ACROSS A BLOOD-BRAIN BARRIER IN VITRO MODEL BASED ON CELL LINE PBMEC/C1-2
Nováková, Iveta ; Štaud, František (advisor) ; Červený, Lukáš (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Candidate: Mgr. Iveta Nováková Consultant: Prof. PharmDr. František Štaud, Ph.D. Title of Thesis: Transport of NSAIDS across a blood-brain barrier in vitro model based on cell line PBMEC/C1-2 The blood-brain barrier (BBB) has a prominent role in regulation of the transport of substances into and out of the central nervous system (CNS). Partly, the BBB inhibits the entrance of substances harmful for the brain, it regulates the delivery of needed substances and it takes part in efflux of useless substances as well. The equilibrium of these regulation systems is essential for the correct function of the CNS, without which the homeostasis would be disturbed. Non-steroidal anti-inflammatory drugs (NSAIDs) are very well known for their anti- inflammatory effect, for reduction of fever and pain. Due to their bright, everyday usage, some side effects on the brain were observed (sleepiness, giddiness, nausea). This has evoked the question, how NSAIDs can cross the BBB. PBMEC/C1-2 cell monolayer was used as an in vitro model of the BBB. The transport of following NSAIDs was investigated: celecoxib, diclofenac, ibuprofen, lornoxicam, meloxicam, piroxicam and tenoxicam. The experiments were carried out...
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Public Media Ownership as an Instrument of Political Contest
Nováková, Iveta ; Švec, Kamil (advisor) ; Mlejnek, Josef (referee)
The connection between world of media and world of politics is unchallengeable. Every politician wants to show himself in the best way in front of the electors. It is understandable that they care about how they are presented in media. There is one opportunity how politicians could influence the media content - they could control part of the media market. And that could be a potential problem. There are many countries which solve this question in recent few years and Czech Republic is not an exception. Andrej Babiš is the chairman of Czech political party ANO and founder of supra-national company Agrofert. He bought one of the biggest and most influence media groups in Czech Republic MAFRA in 2013 (MAFRA contains for example the website iDNES.cz and newspaper Mladá Fronta DNES). Since that time many people talk about Babiš's conflict of interests, which is unacceptable for many politicians, experts and also for many citizens. The main aim of this bachelor thesis is to analyse Czech political scene related with this topic. Theoretical part enables the higher orientation in the world of media and it also provides the information that is necessary for the analytic part of the thesis. On the other side the analytic part concentrates on the Czech Republic and it analyses the specific situation in Czech...
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Transport nesteroidních antiflogistik přes hematoencefalickou bariéru in vitro
Nováková, Iveta ; Štaud, František (advisor) ; Červený, Lukáš (referee)
The migration of substances between the blood circulation and the central nervous system (CNS) is regulated by the blood-brain barrier (BBB). Small, lipophilic molecules such as carbon dioxide, oxygen or ethanol can pass the BBB by passive, transcellular diffusion, while the paracellular transport of hydrophilic substances is restricted by intercellular tight junctions. Due to accessory transport systems, the BBB is able to regulate specifically the permeation of substances (e.g. nutrients) (Ballabh et al., 2004). Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most commonly used substances world-wide, yet little is known about their ability to cross the BBB. Since NSAIDs may exhibit CNS side effects including dizziness, headaches and drowsiness we sought to study the transport of several NSAIDs (celecoxib, diclofenac, ibuprofen, lornoxicam, meloxicam, piroxicam and tenoxicam). Both single studies and group studies were carried out applying either a single substance or several substances simultaneously across the BBB in vitro model based on the human cell line ECV304. The permeability data were normalized to the internal standards diazepam and carboxyfluorescein to account for cell layer's variabilities. According to our studies, it was confirmed that crossing of ibuprofen and...
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ELIMINATION OF NEGATIVE PROPERTIES OF CONCRETE INDUCED BY THE USE OF RECYCLED AGGREGATES USING BASALT FIBERS
Fittl, David ; Nováková, Iveta (referee) ; Bodnárová, Lenka (advisor)
The thesis summarises information about recycled aggregates and basalt fibres, their interaction in composite material such as concrete. It focuses on the potential deficiencies and properties of concrete due to the use of recycled aggregates and on the possibilities of their subsequent elimination of their negative impact by the use of basalt fibres. It characterizes individual raw materials and their interaction in concrete. It includes verification of the properties of the individual sub-components and the resulting concrete itself. An assessment is made of the impact of the use of recycled aggregates on the properties of concrete (compresive strength, static modulus of elasticity, residual flexure tensile strength and others). The thesis discusses the question of whether the same or similar mechanical properties of concrete can be achieved with natural and recycled aggregates using basalt reinforcing fibres. The work provides for the possibility of settlement the values of these concrete parameters by using basalt fibres as a dispersed reinforcement in concrete. The recycled aggregates come from concrete company JARO AS in the north of Norway, where this work was conducted with the financial support from Erasmus+ at The Arctic University of Norway - campus Narvik.
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BEHAVIOUR OF CEMENTITIOUS COMPOSITES EXPOSED TO HIGH TEMPERATURES
Nováková, Iveta ; Chobola, Zdeněk (referee) ; Sitek,, Libor (referee) ; Wallevik, Ólafur Haralds (referee) ; Pimienta, Pierre (referee) ; Bodnárová, Lenka (advisor)
Fire resistance is becoming increasingly important along with the development of new concrete types with high strength and dense structure with reduced porosity. Such concrete types are susceptible to fire spalling and extensive crack formation. At the moment, there are a limited number of methods for enhancement of fire resistance of existing structures, which could be applied in underground structures with restricted space and limited air exchange, such as tunnels, underground garages or nuclear powerplants. This work is focused on the development of two methods, and both are dealing with porous structure modification. The first method is intentional heat treatment (IHT) method, suitable for the enhancement of fire resistance of existing structures. The second method emphasized the design of air-entrained concrete (AeA-FiResCrete) with the use of “new generation” air-entraining agents suitable for enhancement of fire resistance of newly designed concrete. Testing of compressive strength, porous structure modification was completed by the analysis of “moisture clog,” which contributes to explosive spalling and extensive cracking. The efficiency of developing methods was verified during large-scale testing according to modified ISO834 (m-ISO) curve. No extensive crack formation or explosive spalling was observed during the exposure period during the large-scale testing of slabs with the applied IHT method. The total thickness of the IHT method with configuration IHT200/2, composed of IHT zone and IHT transition zone, penetrated to the depth of 25,5 to 43,0 mm depending upon various concrete types. Moisture clog in AeA-FiResCrete was more significant than in the case of slabs with applied IHT method, and it could be concluded that the IHT method enhances fire resistance of concrete exposed to elevated temperatures without influencing its compressive strength and durability. Results from AeA-FiResCrete testing showed only a slight improvement of its fire resistance.
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Population development in Sweden since 1960
Nováková, Iveta ; Kurtinová, Olga (advisor) ; Kalibová, Květa (referee)
Population development in Sweden since 1960 Abstract This diploma thesis deals with the population development in Sweden between 1960 and 2018. The main goal of this work is to evaluate in the context of selected demographic characteristics the course of demographic changes that appeared in the country after 1960. The result is changes in the level of demographic reproduction, which are referred to as the second demographic transition. From the 1960s to the present, Sweden has seen an increase in the average age at first marriage, an increase in the average age of the mother giving birth and an increase in the number of divorces. During the observed period, the Swedish population aged, the share of the pre-productive component of the population decreased, while the share of the post-productive component in the population increased. The development of total fertility in Sweden is often compared to a roller coaster due to its specific fluctuation. From 1960 to 2018, Sweden saw a decline in mortality rates, especially in the older age groups and up to one year of age, which was reflected in the values of life expectancy at birth that grew for both men and women. Sweden is inspiring for other European countries with its gender-neutral family and social policy. Keywords: population development, Sweden, second...
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