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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.
311

Fyziologické, anatomické a morfologické reakce sazenic buku lesního a smrku ztepilého na stres suchem a následnou závlahu =:Physiological, anatomical and morphological response of European beech and Norway spruce seedlings on drought stress and subsequent irrigation /

Hájíčková, Martina January 2019 (has links)
European beech (Fagus sylvatica L.) and Norway spruce (Picea abies (L.) Karst) are the most abundant deciduous and coniferous tree species in the Czech Republic. Both beech and spruce are due to their sensitivity to drought threatened by ongoing climate change that can cause deterioration of their vitality in current habitats. Drought periods are already becoming longer and stronger and previously rare spring droughts become more frequent. The dissertation thesis is based on experiments with Norway spruce and European beech seedling exposed to different levels of drought (well-watered, moderate drought and severe drought). After three to six weeks of drought, the seedlings were well-watered for another two weeks and their response of physiology, anatomy and morphology was evaluated. Experiments were conducted with seedlings at early stage of leaf development and with fully developer leaves to compare response to spring and summer drought. Overall drought response was stronger in spring. Both spring and summer drought reduced gas exchange parameters (in both beech and spruce seedlings up to 100 %), hydraulic conductivity and less strongly also fluorometric parameters. Efficiency of water use in stressed seedlings decreased in spring, while it increased in summer. Shoot and leaves biomass was more reduced by drought than root biomass. Tree-ring width decreased about two times more in beech seedlings than in spruce seedlings. Vessel and tracheids in stem and shoots reduced their number and size, on the contrary, vessel size increased in beech petioles. After rewatering the reduced parameters increased, however, hydraulic conductivity, anatomy and morphology did not reach values of well-watered seedlings. While most of physiological parameters restored in moderately stressed seedlings, in severely stressed seedlings mainly gas exchange parameters remained lower.
312

Vodní režim rekultivovaných a nerekultivovaných výsypek / Water regime of reclaimed and nonreclaimed heaps

Cejpek, Jiří January 2011 (has links)
Summary: Great Podkrusnohorska spoil heaps in the Sokolov region in Western Bohemia is the largest spoil heaps in the Czech Republic, which was pour million tonnes of overburden soil surface mining of brown coal. The thesis is setting on the basic characteristics of the water regime and water balance of spoil heap soil and thus follows a series of previous works dealing with the comparative development of the reclaimed and unreclaimed area. The areas are long-term monitoring of soil moisture using a dielectric soil moisture meter total water regime was monitored by subsurface with gravitation lyzimeter, runoff and throughfall rainfall. Older unreclaimed plots as well as reclaimed plots have higher porosity, water field capacity and moistre than young sites, however there are limited by water deficiency in similatr way as young sites due to increase in wilting point. Keywords: Spoil heaps, Recultivation, Soil humidity, Water supply, Water balance
313

Fotosyntetické charakteristiky fytoplanktonu eutrofních vod / Photosynthetic characteristics of phytoplankton in eutrophic waters

Tesařová, Blanka January 2011 (has links)
Photosynthesis and primary production were estimated in fishpond phytoplankton during period 2008-2010 in Třeboň fishpond region, Czech Republic. Photosynthesis was measured by the oxygen method in computer-assisted light pipetting system Illuminova. Altogether 64 samples of fishpond phytoplankton and 11 cyanobacterial cultures were analysed. Cyanobacteria and chlorococcal algae formed the most important part of phytoplankton biomass and their photosynthesis-irradiance (P-I) curves showed shade-adapted type of P-I curves with the high photosynthetic efficiency. No significant differences in the main parameters of P-I curves were obtained between different types of phytoplankton (chlorococcal-dominated, cyanobacteria- dominated). The results are consistent with the high turbid conditions in eutrophic or hypetrophic fishponds. On the contrary photosynthesis in cyanobacterial cultures differs from "wild" phytoplankton and therefore they can not be taken in primary production models. Primary production was estimated according Talling's model (1957), based on daily measurement of radiation, extinction coefficient of water and seasonal courses of chlorophyll concentration. Photosynthetic capacity and onset of light saturation determined in P-I curves were used as physiological parameters of Talling's model. The...
314

Možnosti odstraňování kovů ze zdrojů pitné vody vodárenskými procesy / Possibilities of removing metals from drinking water sources by water treatment processes

Marzinová, Kristýna January 2022 (has links)
In my diploma thesis I focused on the issue of metals, their occurrence in drinking water sources in the Czech Republic and the possibility of their removal by water supply processes. Heavy metals degrade the quality of water resources, so more complex water treatment technologies are needed. The first part describes the metals, their properties, their significance and occurrence in water, then the possibility of removing metals using water supply processes. In the practical part of the diploma thesis I performed a laboratory experiment to remove iron, manganese and nickel by adsorption on selected filter materials, which are Filtrasorb F100, Filtrasorb F 400, Bayoxide E33 and GEH. The experiment was used to compare the effectiveness of selected sorption materials.
315

Hydraulika solárních systémů / Hydraulics solar systems

Podjuklová, Lucie January 2012 (has links)
The project addresses in the theoretical part of the hydraulics of solar systems and her components, which are used to design a solar system on apartment house. Solar systém addresses praparation hot water in two variants of the solution. In the first alternative solution is used low flow and 15 l/hod.m2 support stratification. In the second variant is used higher flow 20 l/hod.m2 without support stratification. In the experimental part is solved by the data analysis of the same apartment building, where the solar system are already installed and operated. Some data from the measurement was taken into account and used in the design and calculation of both options.
316

Izolační a dielektrické vlastnosti vody / Insulation and dielectric properties of water

Grill, Jiří January 2011 (has links)
This master´s thesis deals about insulation and dielectric properties of water. It describes the structure of water, covalent and hydrogen bonds. It outlines primary chemical and physical properties of water and then it describes parameters of water - dynamic viscosity, conductivity, surface tension, pH and also describes dielectric properties - dielectric loss, loss factor, permittivity, polarization. Part of the work is practical section, which includes measurements of deionized water, destilled water, tap water and shows primary dependence such as dependence loss factor on frequency or relative permittivity on frequency.
317

Zdravotně technické instalace ve studentských kolejích / Sanitation installation in student dormitories

Kucharik, Miroslav January 2015 (has links)
Diploma thesis describes the design of plumbing systems in student dormitories. The theoretical part discusses the types of waste water, focusing on gray water and its subsequent use. The experimental part is focused on measurement drinking water consumption and drinking water discharge in existing buildings student dormitories and apartment building. The work also contains other variants of possible installation solutions. The project is part of the selected solutions developed a variant form of project documentation for construction.
318

Zdravotně technické instalace v bytovém domě s komerčními prostory / Sanitation installation in an apartment building with commercial space

Valášek, Martin January 2015 (has links)
This thesis describes the design of plumbing in an apartment building with commercial space in Ilava. The theoretical part is devoted to the design of the container hot drinking water and it´s possible alternatives. The work also focuses on possible solutions diploma work. Computational part of a project proposal contains sewage and rainwater drainage, water supply systems and connecting the building to the existing network hardware. It is a residential house, which is in part intended for commercial premises and the second part is intended for housing. The building has four floors and no basement.
319

Koupání dětí v krytých bazénech / Bathing of children in indoor swimming pools.

OHEROVÁ, Martina January 2016 (has links)
This diploma thesis deals with bathing children, especially infants and toddlers, in indoor swimming pools. It focuses primarily on the potential health and hygiene risks of this activity. It is divided into theoretical and practical part. The theoretical part provides a deeper insight into the field of artificial swimming pools, is dedicated to current as well as first ever legislation, in more detail is dedicated to the hygienic requirements for swimming pools according to Decree no. 238/2011, as amended; describes the process of pool water treatment, provides an overview of possible types of disinfecting pool water treatment and comparison within the advantages and disadvantages, describes indicators of water quality and their importance, and mostly focuses on hygienic and health risks in connection with the visit of indoor pools. Gives examples from practice (epidemic), mentions the most common sources of pollution including the most common violations of visitors. The theme of hygienic and health risks is then divided according to the origin of risk to the microbiological part (dedicated to infectious agents), to chemical part (disinfection by products) and to the part of accident risks and risks associated with the water temperature. The thesis is also keenly interested in the views of experts for bathing children, especially infants and toddlers, in indoor artificial pools. Research in the practical part was made by a qualitative method using secondary data analysis (operational and guest regulations, operational logbooks for 2015, the results of laboratory analysis of pool water for the 2015, laws and decrees), participant observation and interviews. The research was conducted in indoor swimming pools in towns Jihlava and Prachatice, which run swimming courses for infants and toddlers as well as for older children. For research, I set the following goals: C1: To monitor the microbiological and the physical-chemical indicators of the pool water quality in relation to Decree no. 238/2011 Coll., as amended, in pre-selected artificial indoor pools during annual operation. C2: To focus on the health status of children (infants and toddlers) in swimming classes. C3: To find out the knowledge and attitudes of visitors (parents) and trainers in the field of hygiene principles for swimming in artificial pools and risks arising from them. Based on the targets I have set the following research questions: V1: Are the monitored microbiological and physico-chemical water quality limits exceeded, and if so, which and under what circumstances? V2: What health problems, if they occured, did infants and toddlers after regular visits of indoor pools have ? V3: Are these children suffering from allergic diseases, and if so, from what type? V4: What knowledge and attitudes do visitors (parents) and lecturers in the field of hygienic principles for swimming in artificial pools and potential risks have? This thesis may serve the general public to extend the knowledge in the field of bathing (not only the children) in artificial pools and to give a view on this subject from different perspectives, as well as operators of swimming pools as an information material.
320

Trigenerace a její využití v praxi / Trigeneration and its use in practice

Čupera, Pavel January 2009 (has links)
e master's thesis clarifies the concept of trigeneration and the principle of absorbing cooling. Compare the advantages and disadvantages of this method of manufacture cool with compressor cooling. It presents an overview of the implementation of a developing cold absorption and performance. Acquainted with the types of absorption chillers of the two leading suppliers, their characteristics and existing applications of these refrigeration units in operation in the Czech Republic and abroad. It also assesses the possibility of using these units in conjunction with a cogeneration unit powered by internal combustion engine. It follows from the economic assessment of costs and income of the absorption chillers and compressor chillers and on concrete examples and an assessment of the effectiveness of the various options.

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