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Effect of temperature on electrochemical parameters of Li-S battery
Bečan, Jan ; Skala, Kateřina (referee) ; Jaššo, Kamil (advisor)
This bachelor's thesis deals with the production of lithium-sulfur battery and the effect of changing temperatures on its electrochemical parameters. The theoretical part is focused on primary and secondary batteries and their historical evolution, anode and cathode materials for lithium-ion batteries and next-generation batteries. The practical part is focused on preparing the electrode material for lithium-sulfur battery, completion of electrochemical cell and measuring the values of cycling charge/discharge at different temperatures.
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Preparation and characterisation of electrode materials based on elementar sulphur for Li-ion cells
Jankulár, Tomáš ; Vondrák, Jiří (referee) ; Čech, Ondřej (advisor)
This thesis deals with the preparation and characterization of electrode materials for Li-ion batteries based on elemental sulfur. The theoretical part is focused on the characteristics of Li-ion batteries, electrochemical reactions, the process of electrochemical lithiation of sulfur and solubility properties of intermediate polysulfides. The practical part of the thesis deals with the preparation of cathode materials for Li-ion cells with an active substance in the form of elemental sulfur. The prepared electrodes were investigated using cyclic voltammetry and galvanostatic cycling. Physical characterization by SEM and XRD was provided.
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Determination of the most suitable ratio of cathode materials for the lithium-sulfur battery system
Benešová, Petra ; Kazda, Tomáš (referee) ; Jaššo, Kamil (advisor)
This master's thesis deals with a topic of determination of the most suitable ratio of cathode materials for the lithium-sulfur systems. The first two chapters provide a general introduction to the topic of electrochemical energy sources and present the commonly used primary and secondary battery systems with emphasis on their characteristics and applications. The core of the theoretical part is dedicated to lithium-ion and lithium-sulfur batteries, their working principles along with the benefits or drawbacks related to the particular systems, and widely used materials. The experimental part briefly comments on determining the suitable electrode paste preparation method, the subsequent main part is focused on evaluation of electrochemical performance of cells using different ratios of cathode materials. Five samples of cathode materials were prepared, where the sulfur ratio is in range from 64 to 88 wt. %. Finally, the comparison of all prepared ratios in terms of their electrochemical properties is provided.
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Electrode Materials for Li-S Batteries
Jaššo, Kamil ; Almáši,, Miroslav (referee) ; Syrový,, Tomáš (referee) ; Kazda, Tomáš (advisor)
This thesis is focused on the research of electrode materials for lithium-sulphur (Li-S) batteries, with an emphasis on the optimization of the process of preparation of positive electrodes through the modification of the individual technical steps of the manufacturing process and the selection of a suitable binder. The theoretical part of the thesis is devoted to terminology and battery issues with emphasis on Li-S batteries, their working principle, shortcomings, critical parameters for commercialization and existing research in this field. The practical part of the thesis deals with the influence of the compression pressure used in the production of positive electrodes on the electrochemical properties of the resulting Li-S cells. In the next part of the thesis, the influence of the binder used on the resulting electrochemical properties is investigated. In the following sections, the influence of the thickness of the electrode material layer and the ratio of its individual components (C/S) on the resulting electrochemical properties of the Li-S cell is analyzed. On the basis of the measured results, the optimum conditions for the preparation of the positive electrodes of the Li-S cells have been identified with respect to the individual technical steps of the manufacturing process.
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Ověření účinnosti různých inhibitorů nitrifikace v hnojivu DASA na výnos a kvalitu zrna pšenice ozimé
Kvita, Martin
The bachelor thesis deals with the effect of different nitrification inhibitors in the fertilizer DASA on the yield and grain quality of winter wheat (Triticum aestivum). The practical part was solved in the form of a small-plot field experiment at the Field Experimental Station Žabčice in the 2021/2022 growing season. The parameters were assessed: the grain yield, the hectoliter weight of the grain, the content of protein and gluten in the grain and the Zeleny test. The fertilizer variants included in the experiment were: 1. DASA (control variant without inhibitors), 2. DASA + MPCAA 1, 3. DASA + MPCAA 2, 4. DASA + DMPP, 5. DASA + DMPPA, 6. DASA + MPA 1, 7. DASA + MPA 2. Winter wheat grain yield was not statistically significant. The highest average value was achieved by variant No. 7 DASA + MPA 2 (6.80 t.ha-1). Compared to the control variant, it achieved a higher yield by 0.18 t.ha-1. The highest values of hectolitre weight of grain were observed for the control variant No. 1 DASA (77.1 kg.hl-1). The content of protein was highest in control variant No. 1 DASA and variant No. 6 DASA + MPCAA 1 (12.2%). The highest gluten content (26.8%) and sedimentation value (37 ml) was also achieved by control variant No. 1 DASA. In terms of yield, variant No. 7 DASA with MPA 2 inhibitor had the highest values, while the highest values in terms of quality were achieved by variant No. 1 DASA without inhibitors.
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Srovnání účinnosti vybraných systémů hnojení na produkci a kvalitu pšenice ozimé
Horký, Jiří
The aim of this diploma thesis was to evaluate the influence of different fertilization options on the yield and quality of winter wheat grain and the profitability of its cultivation. Among the qualitative parameters, the content of nitrogenous substances, gluten and sedimentation value were monitored. The research took place in the form of a one-year semi-operational field experiment in the Jabloňov area, Vysočina. The following five fertilization variants were included in the experiment: LAV as control, urea, DASA (ammonium nitrate with ammonium sulfate), Urea stabil (urea with urease inhibitor) and ENSIN (ammonium nitrate with ammonium sulfate and nitrification inhibitor). The results show that the fertilization variants had no effect on the size of the yield. The effect of nitrification and urease inhibitors and sulfur fertilizers on grain quality parameters was also inconclusive (compared to the LAV control). A significant increase in quality parameters was noticed when comparing fertilizers with inhibitors and their equivalents without inhibitors. The ENSIN variant contained 4,3 % more nitrogenous substances and 8,3 % more gluten than the DASA variant. The Urea stabil variant contained 8,2 % more nitrogenous substances, 9,5 % more gluten and achieved a 12,2 % higher sedimentation value than the urea variant. Economically, the DASA variant turned out to be the best option. Fertilizers with inhibitors had a rather negative effect on the economics of cultivation
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Využití kombinovaného hnojiva ve výživě řepky ozimé
Dundálek, Ladislav
The diploma thesis aimed to evaluate the effect of regeneratively applied combined fertilizer in the nutrition of oilseed rape. The experiment was established at two localities (Žabčice and Vatín) in the form of a small-plot field experiment carried out in the economic years 2020/2021 and 2021/2022. The following treatments were included in the experiment: unfertilized, control, FertiTOP 44 NPS, and FertiTOP 44 NPS in lower dose. The total dose of nitrogen applied in treatment FertiTOP NPS 44 (lower dose) was 130 kg/ha. Control treatment and FertiTop NPS 44 in full dose were based on the total dose of 168 kg/ha of N. In addition to nitrogen, sulfur was also applied as part of regenerative fertilization in control treatment. The following parameters were examined: yield, oil content, oil production, and economic evaluation. A statistically significant difference between the examined treatments was found for the yield and oil production parameters. Overall, the FertiTOP 44 NPS (full dose) treatment was evaluated as the most optimal option with the highest average yield of 3.81 t/ha recorded in the Vatín location. At the Žabčice location, this variant provided an average yield of 3.20 t/ha. This variant was evaluated for the second highest oil content in the Vatín locality (45.3%), but in the Žabčice locality, this variant provided lower oil content (40.7%). In terms of oil production, the FertiTOP 44 NPS (full dose) treatment showed the highest oil production at both locations. The application of FertiTOP 44 NPS resulted in the average oil production 1.72 t/ha in Vatín and 1.31 t/ha in Žabčice. The economic evaluation showed that application of FertiTOP 44 NPS resulted in increase of profit by 21.21% compared to the control treatment in the economic year 2020/2021. Similar result was observed in second year (2021/2022), but the increase in profit compared to the control variant was only 4.11%.
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Kompozity nanouhlíkatých materiálů pro ochranu zemědělských rostlin před houbovými patogeny
Burešová, Michaela
Graphene oxide (GO) belongs to carbon-based nanomaterials (CBNs) and is capable of bonding with various molecules, thanks to the presence of functional oxygen groups in its structure, created during graphene oxidation. This mechanism can be applied on nutrient and pesticide delivery and improve their utilization by plants. Sulphur is an essential nutrient and also has fungicidal properties. In this study, graphene oxide was synthesized and used to make two nanocomposites containing sulphur. GO and nanocomposites were then characterized. Nanocomposites were tested for phytotoxicity, and their potential fungicidal properties were studied. Both nanocomposites showed significant fungistatic effect against grey mold when tested on plates with medium. However, when tomato leaves were treated with nanocomposites, inhibition effect against mycelium growth was ineffective.
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The Impact of the IMO-2020 Shipping Regulation on the Atmospheric Deposition of Sulfur around the Western English Channel and the Use of the V/Ni ratio as a Shipping Marker.
Windell, L. ; Bell, T. ; White, C. ; Schwarz, Jaroslav ; Ussher, S.
Anthropogenic aerosols are shown to have a great impact on marine ecosystems and human health, with the shipping industry contributing as a significant source of these\nemissions, and annual growth on the rise. In the marine environment, shipping emissions often dominate atmospheric deposition of sulfur. With around 70% of shipping activity\nbeing carried out within 400 km of the coast, its contribution to atmospheric sulfur is of great interest. The International Maritime Organisation (IMO) introduced a regulation on\n01/01/2020 restricting global marine fuel sulfur content from 3.5% to 0.5% w/w. The vanadium/nickel (V/Ni) ratio has been widely used as a marker of shipping emissions, with the range of 2.5 to 4 indicating shipping activity. The regulation has called into question the viability of the earlier use of the V/Ni ratio.
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