Solid fuels boilers

Tato bakalářská práce se zabývá spalováním tuhých paliv v kotlích pro vytápění rodinných domů. V první kapitole jsou popsány jednotlivé druhy tuhých paliv z hlediska jejich složení, vlastností, způsobů využití k energetickým účelům a jejich úpravy do podoby vhodné ke spalování. Ve druhé kapitole jsou popsány jednotlivé druhy zařízení pro spalování tuhých paliv. Poslední kapitola se zabývá porovnáním vybraných kotlů z hlediska pořizovacích nákladů a nákladů na jejich provoz.This bachelor’s thesis deals with burning solid fuels in boilers used for house heating. In the first chapter, the individual kinds of solid fuels are described in light of their composition, properties, means of their energetical application and ways of adjusting them to a form proper for combustion. In the second chapter, the individual types of solid fuels boilers are described. The last chapter deals with comparision of several specific boilers in light of their purchase price and operating expenses.

Applications for Wearable Devices based on Android Wear OS

Semestrální práce „Aplikace pro nositelnou elektroniku se systémem" Android Wear popisuje základní principy komunikačních sítí - M2M (machine to machine), H2H (human to human) a D2D (device to device). Práce se dále zabývá nositelnými zařízeními, zejména chytrými hodinkami, dostupnými operačními systémy pro chytré hodinky a systémem Android, Android Wear. V praktické části je popsaná funkcionalita, vzhled a struktura vyvinuté aplikace pro Android Wear.The semestral project "Application for Android Wear wearables” describes basic principles of the communication network - M2M (machine to machine), H2H (human to human) and D2D (device to device). It is also focused on wearables especially smart watches, available operation systems for smart watches and system Android, Android Wear. In the practical part is described functionality, design and structure of developed application for Android wear smartwatch.

Compression behaviour and failure mechanisms of a safety culvert made of hollow high-performance concrete blocks

The safety culvert composed of hollow high-performance concrete blocks is designed to reduce the risk of injury in the event of a collision. This work presents a new design with an opening for water flow, tests it, identifies its weaknesses, and discusses possible improvements. The numerical model is constructed, validated by experiment, and used to study the effect of design parameters on the load capacity, compression behaviour, and failure mechanisms. The response varies most markedly with the opening diameter. The failure mode changes from bending failure to concrete crushing as the diameter decreases. The effect is most pronounced for diameters less than 400 mm, where the load capacity increases by 6 kN per millimetre reduction. If a crack develops in the culvert during its service life, the first such crack will form in the top layer of blocks, followed by a crack in the opening. These areas should be monitored more closely during follow-up tests with passing vehicles

Compression behaviour and failure mechanisms of a safety culvert made of hollow high-performance concrete blocks

The safety culvert composed of hollow high-performance concrete blocks is designed to reduce the risk of injury in the event of a collision. This work presents a new design with an opening for water flow, tests it, identifies its weaknesses, and discusses possible improvements. The numerical model is constructed, validated by experiment, and used to study the effect of design parameters on the load capacity, compression behaviour, and failure mechanisms. The response varies most markedly with the opening diameter. The failure mode changes from bending failure to concrete crushing as the diameter decreases. The effect is most pronounced for diameters less than 400 mm, where the load capacity increases by 6 kN per millimetre reduction. If a crack develops in the culvert during its service life, the first such crack will form in the top layer of blocks, followed by a crack in the opening. These areas should be monitored more closely during follow-up tests with passing vehicles

Flavonoid glycosides from endemic bulgarian astragalus aitosensis (Ivanisch.)

© 2019 The Author(s). Background: The activity and haemolytic toxicity associated with primaquine has been linked to its reactive metabolites. The reactive metabolites are thought to be primarily formed through the action of cytochrome P 450 -mediated pathways. Human erythrocytes generally are not considered a significant contributor to drug biotransformation. As erythrocytes are the target of primaquine toxicity, the ability of erythrocytes to mediate the formation of reactive oxidative primaquine metabolites in the absence of hepatic enzymes, was evaluated. Methods: Primaquine and its enantiomers were incubated separately with human red blood cells and haemoglobin. Post-incubation analysis was performed with UPLC-MS/MS to identify products of biotransformation. Results: The major metabolite detected was identified as primaquine-5,6-orthoquinone, reflecting the pathway yielding putative active and haematotoxic metabolites of primaquine, which was formed by oxidative demethylation of 5-hydroxyprimaquine. Incubation of primaquine with haemoglobin in a cell-free system yielded similar results. It appears that the observed biotransformation is due to non-enzymatic processes, perhaps due to reactive oxygen species (ROS) present in erythrocytes or in the haemoglobin incubates. Conclusion: This study presents new evidence that primaquine-5,6-orthoquinone, the metabolite of primaquine reflecting the oxidative biotransformation pathway, is generated in erythrocytes, probably by non-enzymatic means, and may not require transport from the liver or other tissues

A simple fish-based approach to assess the ecological quality of freshwater reservoirs in Central Europe

The assessment of ecological quality in freshwater ecosystems is a key issue in many countries, but conditions for the development of assessment methodologies are often country-specific. This study proposes a simple methodology for the assessment of the ecological potential of reservoirs based on fish communities using a dataset covering major environmental and pressure gradients in reservoirs in the Czech Republic. Fish data obtained by gillnet sampling were correlated with a proxy of eutrophication as a key indicator of anthropogenic pressure for selecting appropriate fish-based indicators, establishing scoring criteria and developing the index of ecological quality. Expert judgement was also used to select potential fish indicators. Nine indicators were selected for the final fish-based index, fulfilling the criteria required by the Water Framework Directive. Two steps were used to validate the fish-based index quantification of its inter annual stability and sensitivity analysis of individual indicators. Finally, the index was compared to a previously developed general index for Central and Western Europe. Our study demonstrates that a combination of expert judgement and strict validation methods can result in an informative assessment of the ecological conditions, which can help identify conservation and restoration priorities. © P. Blabolil

Long-term monitoring of fish in a freshwater reservoir: Different ways of weighting complex spatial samples

Anthropogenic activities continue to pose the greatest challenges to freshwater ecosystems. Therefore, long-term monitoring is essential for the management and conservation of these resources. Monitoring programs for freshwater bodies often use a range of indicators, including biological elements such as fish. Existing European standard provides a depth-stratified gillnet sampling approach mainly in benthic habitats and at the deepest part of lakes to account for the uneven distribution of fish. However, the commonly used CEN (European Committee for Standardization) protocol does not weight sufficiently habitat volumes and underrepresent pelagic habitats to calculate whole-lake catch and biomass per unit effort (CPUE and BPUE, respectively). Extended European standard gillnet (4 larger mesh-sizes added in the geometric series) catch data collected over 18 years (2004–2021) in Římov Reservoir (Czech Republic) were used for a method comparison on indices for relative abundance and biomass of fish: CEN protocol without volume-weighting and two volume-weighted approaches. We also evaluated changes in species composition and trends in these fish population over time. Results indicated interannual changes in species composition, relative abundance, and biomass of fish community. The CEN protocol tended to put greater emphasis on benthic habitats which generally have larger CPUE and BPUE. Consequently, the two volume-weighting approaches produced lower estimates of the two parameters, with the exception of the most dominant pelagic bleak Alburnus alburnus (L.). All approaches consistently showed an increasing trend in whole-reservoir fish abundance and a decreasing trend in biomass over the study period. Following our assessment, we put forward the volume-weighting approach that considers the Volume of the depth Stratum (VOST) for weighting as the most realistic approximation of fish populations and therefore recommend its use

Observation of a spontaneous anomalous Hall response in the Mn5Si3 d-wave altermagnet candidate

Phases with spontaneous time-reversal (T ) symmetry breaking are sought after for their anomalous physical properties, low-dissipation electronic and spin responses, and information-technology applications. Recently predicted altermagnetic phase features an unconventional and attractive combination of a strong T -symmetry breaking in the electronic structure and a zero or only weak-relativistic magnetization. In this work, we experimentally observe the anomalous Hall effect, a prominent representative of the T -symmetry breaking responses, in the absence of an external magnetic field in epitaxial thin-film Mn5Si3 with a vanishingly small net magnetic moment. By symmetry analysis and first-principles calculations we demonstrate that the unconventional d-wave altermagnetic phase is consistent with the experimental structural and magnetic characterization of the Mn5Si3 epilayers, and that the theoretical anomalous Hall conductivity generated by the phase is sizable, in agreement with experiment. An analogy with unconventional d-wave superconductivity suggests that our identification of a candidate of unconventional d-wave altermagnetism points towards a new chapter of research and applications of magnetic phases