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Polymer protective systems for concrete floors
Novotná, Adéla ; Vyhnánek, Miroslav (referee) ; Petránek, Vít (advisor)
The thesis is addressing the testing of protective polymer layers, which are used mainly for industrial floors. A summary table of standards is presented, dividing the test carried out on the binders, fillers, fresh mixture and polymerized material. Non standardize tests are described in detail in a very similar way as it is performed by the Institute of Technology of Building Materials and Components. The second part of my thesis is devoted to testing of the reference material and material filled with raw substances. Based on recommendations of Lena Chemical Company, filler – ground windscreen glass will be used. On this type of mixture selected set of tests needed for construction and technical certificates was performed.
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Business Plan for Establishment of the Company
Koukal, David ; Navrátil, Jaroslav (referee) ; Rompotl, Jaroslav (advisor)
This thesis defines the theoretical basis essential for building a business plan and simultaneously encompasses the building of a real business plan, which will be focused on the creation of a new company - KK-TECH s.r.o., which will offer complex cleaning services. The key aspect of the thesis is market analysis, which the company will enter, and a marketing and financial plan. I will use primarily data, which have been obtained while studying, and also data, which have been obtained thanks to working in said field.
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Porovnání účinnosti metod extrakce tropických dřev na základě analýzy získaného extraktu a jeho vlivu na dřevokazné houby
Přibylová, Zdeňka
The thesis compares the efficiency of two extraction methods: using the FexIKA apparatus and using ultrasound. To compare the extraction methods, extracts from merbau (Intsia bijuga O.Ktze.) and jatoba (Hymenaea courbaril L.) were created. These tropical woods were ground and extracted. From the extracts, three concentrations of protective substances were created. The protective substances were tested to determine the content of extractive compounds and polyphenolic compounds. The obtained protective substances were impregnated into the wood of common beech (Fagus sylvatica L.) and pine (Pinus sylvestris L.). The impregnated beech and pine samples were tested to determine the protective effectiveness against Trametes versicolor L. and Coniophora puteana P. Karst. From the acquired data, the loss of mass of the wood was assessed. The results showed that only samples impregnated with the protective substance with concentration of 3 showed adequate protection. Analysis of the protective substances showed a higher yield when using FexIKA on Merbau wood. Jatoba wood extraction showed a slightly higher yield when extracting using ultrasound. In general, the samples impregnated with extracts obtained using FexIKA showed lower mass loss than samples impregnated with extracts obtained using ultrasound.
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Wood Extractive Compounds - Extraction, Chemical composition, Biological activity, Native durability =: Extraktivní látky dřeva: Extrakce, Chemické složení, Biotická aktivita, Přirozená trvanlivost /
Sablík, Pavel
Wood chemical composition research is of significant importance for various fields like wood-manufacturing, food and pharmaceutical industries. Much research work has been motivated by the fundamental knowledge that wood of some tree species demonstrate significantly higher native durability against biological degradation and therefore is much convenient to use in more demanding applications, e.g. in contact with soil or water. This important wood property was assign mainly to presence of extractive chemical compounds or secondary metabolites, produced by wood when heartwood is formed. The presented doctoral thesis aims to find the possibilities of how to utilize extractive chemical compounds found in Black locust (Robinia pseudoacacia L.) as treatment solutions. These can be used to increase the durability of low durable wood species. The experimental part of the presented thesis was carried out using the laboraties and equipment of the Mendel University in Brno, and their external laboratories of research centre in Útěchov. Paper 01 aims to establish methodology for extraction apparatus fexIKA. Describes mainly possibilities for quantitative gains of extractives when using various organic solvents. Within this papers research scope heartwood, sapwood and bark of Black locust were used as the source material. Black locust was choosen mainly due to its extremely high native durability, together with oak considered highest in Central Europe, and for longer term experimental plans and reason. The established methodology for primal solvents (acetone, benzene, cyclohexane, ethanol and distilled water) was the result of this paper. The influence of extraction inputs (particles size, solvent type and temperature) on quantitative and qualitative result of extraction process was the topic for research design presented in Paper 02. In the paper comparable results with literature and established fexIKA methodology were proven. Also the effect of the above mentioned inputs are described and extracted chemical content was identified using HPLC-HRMS technique. The possibility of utilizing chemical compounds obtained, based on Paper 01 extractive methodology, aimed for higher content of phenolic compounds according to Paper 02 results, were the topic of Paper 03. This research paper proves antifungal activity of Black locust (Robinia pseudoacacia L.) and African padauk (Pterocarpus soyauxii Taub.) extracts after impregnation into European beech (Fagus sylvatica L.) sapwood. This wood species is assessed as class 5 (not durable), with an average mass loss result after the durability test of untreated samples 43.6 %. Native durability of European beech wood was significantly improved after impregnation with extractives, mass loss resulted in average 12.7 %. This revalued treated beech sapwood into durability class 3. Paper 04 continues with a study of extractives retention in wood matrix after impregnation whilst introducing adjusted leaching tests. Despite standard EN 84, this research employed miniaturized Bravery wood blocks for impregnation and leaching tests, which were at the end shortened to 144 hours. In order to increase the biologicaly active chemical compounds retention in the specimens, heat treatment was used. The results of the experiment proved the significance between heat treatment and retention.
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Wood impregnation
Pařil, Petr
Wood impregnation is one of the oldest and the most frequently used techniques to protect the wood. This treatment offers a wide range of protection depending on used impregnants (preservatives). Impregnation can make the wood more resistant to decay, less flammable, more dimensionally stable, harder, stronger, more UV stable resistant and many more. Generally, the aims of this thesis is to give a new and modern approaches to already known technologies. The experimental part have been carried out using laboratory vacuum-pressure impregnation plant and many other devices. Almost all treatments and measurement have been done in laboratories of Research centre in Útěchov. The different wood species e.g. European beech (Fagus sylvatica L.) and hybrid poplar (Populus hybrids) have been studied. The patented solution shows the method of the treatment and colouring of wood containing tannins, characterized by impregnation with a product containing iron oxide nanoparticles, in a concentration of 0.4 g/l to 42 g/l, an average particle size in the range of 1 to 100 nm, and a liquid medium. Impregnation can be performed as pressure impregnation, followed by soaking, or the product can be applied by brushing or spraying. This method is an alternative to wood ammonification. The tests (Paper I) shows following results. Both nanoiron and ammonia treatments tested induced darker colouring of oak wood, more intensive darkening was observed in case of the nano-iron treatment. The native oak showed a steep drop in lightness ca 25-50 hours of exposure followed by gradual re-increase during further exposure to the artificial sunlight. The darker surfaces generated by tannin reacting chemically with iron and ammonia evidently faded in the course of light exposure. In case of chromatic parameters a* and b*, the AT (ammonia treatment) oak more or less copied the colour change progress of native oak. On the contrary, the NIT (nanoiron treatment) wood showed a double increase in both parameters. The colour of NIT wood after light exposure was more or less equivalent to the original colour of the ammonium-treated. Distinct reddening of NIT oak may be caused by oxidation of non-precipitated iron particles. The antifungal effects of copper and silver nanoparticles against two wood-rotting fungi were investigated with following results (Paper II). The highest value of retention was observed for pine sapwood (~ 2 kg/m3) for both nanoparticle solutions. The amount of nanoparticles in the wood did not increase proportionally with an increasing concentration, but only 1.5-2 times increase was reached. An average leaching of 15% to 35% was observed for copper nanoparticles, depending on used wood species and concentration. Significantly lower leaching (max. 15 %) was observed for pine sapwood impregnated by silver nanoparticles with a concentration of 3 g/l. The highest antifungal effect (under 5 % of mass loss) against both tested fungi was found for nano-copper treatment at the concentration of 3 g/l. However, this effect of treatment seems to be almost negligible after the leaching test. Therefore, this study aims to present fundamental material properties of wood treated with copper and silver nanoparticles, and provide groundwork for further research (e.g. fixation of substances in the wood structure, etc.). In this study (Paper III), selected physical and mechanical properties, i.e., density profile, bending strength, hardness and moisture absorption were investigated for Lignamon (i), which was obtained from the Czech industrial production. Selected properties were also investigated using steam-densified beech (ii) and native beech (iii) and compared with each other. Densitometry of Lignamon showed a large variability of the density profile compared to the density profile of only densified beech. It is affected by the degree of densification, temperature and moisture gradients, and their relationship to the glass transition of the wood cell wall. Modulus of elasticity, hardness, moisture exclusion and anti-swelling efficiency of Lignamon are enhanced compared to densified beech. The enhanced dimension stability and lower hygroscopicity of Lignamon are probably caused by heat treatment during the process. Further investigation will be carried out with self-produced Lignamon samples. The paper IV deals with the effect of vacuum-pressure impregnation of poplar wood (Populus alba L.) by aqueous solutions of sucrose and sodium chloride on its physical properties. The most satisfying final properties were achieved in impregnation of sucrose with concentration of 6.25 g/100 ml H2O. The retention was 31 kg/m3 (WPG around 8 %). The values of ASE (anti-swelling efficiency) reached to 36 % and MEE (moisture exclusion efficiency) was reduced by 33 %. In Paper V, MW and conventional acetylation of wood was carried out to determine its efficacy on the material properties. Both MW and conventional heating positively affected the selected material properties. The results showed that no significant differences were found between MW and conventional heating; therefore, MW heating can be used as a valid replacement in the acetylation process. MW power of 2 kW and 0.1 m/min conveyor speed were the optimum conditions for MW acetylation. These process parameters resulted in 39.4 % ASE (T) and 35.2 % ASE (R) for beech and 38.0 % ASE (T) and 16.3 % ASE (R) for poplar samples. This work provides insight into the details of wood acetylation using MW heating. The study (Paper VI) aims to evaluate the antifungal activity of extractive compounds obtained with fexIKA accelerate extraction process. Results showed that the extractive compounds obtained from black locust heartwood were able to increase the native durability of European beech from class 5 (i.e. not durable with an average mass loss of 43.6 %) to class 3 (i.e. moderately durable with an average mass loss of 12.7 %). The final Paper VII shows following results. After impregnation with residual liquids and leaching, high amounts of TT (thermal treatment) and HTC (hydrothermal carbonisation) solution were washed out, whereas Pyrolysis liquids stayed with 25 % to 40 % remaining in the wood. Volumetric swelling in 65 % relative humidity at 20 °C was reduced from 6.5 % in untreated poplar to 5 % in impregnated samples with process residues of thermal treatment using 180 °C or 200 °C. The processes using HTC liquids from Miscanthus sp. (Misc.) or Sawdust showed reduction to 3-3.5 % and Pyrolysis liquid treatment to 2.5 %. After exposure to fungi, the mass loss of untreated Beech (30-35 %) and Poplar (40-50 %) was reduced to 2 % in case of Pyrolysis- and 4 % in case of TT-treatment.
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Histological examination of the brain for Alzheimer´s disease
HAVELKOVÁ, Kristýna
In my bachelor thesis I deal with histological examination of the brain for the Alzheimer´s disease. I conducted the research at the Department of pathology at the hospital in Jindřichův Hradec. The thesis is divided into two parts theoretical and practical part. In the theoretical part I deal with this, what is actually histology and histological examination, histological structure of the nervous system and especially the brain. I also deal with Alzheimer´s disease, its description, types, symptoms, therapy and prevention. I also mention the Czech Alzheimer Society and myths about Alzheimer´s disease. At the end of the theoretical part, I give the examples of other dementias. In the practical part I performed the histological examination of the brain using methods of Impregnation of nerve fibers by Palmgren and Proof of senile druses by A. v. Braunmühl on frozen sections. These two methods serve to stain the nerve structures (including the druses which are typical for Alzheimer´s disease) which can confirm or deny this disease. I also did a basic staining with Hematoxylin-eosin. This staining was preceded by the processing of biological material such as fixation, trimming (with scalpel), packing, embedding in paraffin, slicing and stretching of the preparation on the slide glass. After staining, the preparation was mounted under the cover glass and then we performed evaluation using a microscope. The aim of my bachelor thesis was to write a research on a given topic, to describe the processing of the brain in the histological laboratory, to perform methods that are typical for Alzheimer´s disease for deceased persons, to evaluate and compare the preparations of the healthy and diseased brain.
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Využití extraktivních látek tropických dřev pro zvýšení přirozené trvanlivosti buku
Přibylová, Zdeňka
This Bachelor thesis focuses on evaluating antimycotic activity of extractive compounds acquired using the FexIKA extraction apparatus. Merbau (Intsia bijuga O.Ktze.) and jatoba (Hymenaea courbaril L.) were used as the sampled material. The extractive compounds were obtained from ground samples of the tropical woods. Then, the beech wood was impregnated with the compounds. A rapid durability test of vulnerability against Trametes versicolor L. was performed. From the data acquired, the weight loss of the impregnated samples and reference samples was evaluated. The results show that the extractive compounds procured from Merbau wood in the highest concentration were able to increase the natural durability of beech from class 5, i.e. not durable, to class 1 - very durable. Impregnation with extractives from Jatoba in the highest concentration level increased the durability from class 5 to class 2, i.e. durable.
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Vliv tepelné modifikace na vybrané vlastnosti bukového dřeva tlakově impregnovaného přírodními oleji
Daněk, Václav
Present study aims to analyze thermal modification of beech wood (Fagus sylvatica L.) press-impregnated by natural oil and its influence on physical and mechanical properties of wood. Beech wood was press-impregnated by hemp oil (O 1000) and thermally modified at 200°C for 3 hours. Influence of certain treatment (i.e. oil impregnation, thermal modification, combination) was experimentally investigated using physical and mechanical tests. Color changes (CIELab system), dimensional stability and bending strength were experimentally measured and results compared with reference group. Results of given work was further discussed and compared with literature. Results shows increase of dimensional stability about 18% after thermal modification (TM) and 22% for oil impregnated and thermally modified wood (OL+TM). Mechanical performance (bending strength) decreased about 5,2% after thermal modification as a results of degradation of wood cell wall. On the other hand, strength increase about 9% for wood impregnated by oils. Combined processed provide results within similar range as reference. Results should be further discussed and parameters of process (temperature levels) as well as influence of various oils parameters (drying, semi-drying, nondrying) tested in future.
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