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Vliv ligninu ve funkci plniva na pevnost lepených spojů materiálů na bázi dřeva
Klonová, Sára
Analysis of the effect of lignin added in various amount to binders containing thermoreactive resins commonly used for bonding wood-based materials is a main theme of this thesis. Itʼs also related to a similar problem analysed in the bachelor thesis – influence of added lignin into heat-activated adhesives, so it can complete already obtained results with some new findings by a change of analysed wood-based material. Practical part of this thesis is focused on a strength of adhesive joints bonded with binders that contain different amount of lignin. Adhesives are applied on a surface of testing samples made of ash and larch and then climatized in a various moisture condition. The tensile strength, shear tensile strength and flexural strength of adhesive joints are being tested. Thesis provides application of obtained results of utilisation of lignin as filler of adhesives used for bonding wood-based materials exposed to specific physical – mechanical factors in practice.
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Vplyv extrémneho umyvacieho procesu na pevnosť v ohybe lepeného spoja v listnatom dreve
Tuhý, Dušan
The diploma thesis is focused on the issue of the effect of the washing process on the bending strength of the glued joint in a special solid wood panel made of hardwood. The goal was to analyze currently available adhesives and types of joints in solid wood panels and to deal with the issue of the washing process and its influence. The selected glue was PVAc glue Rakoll ® GXL 4 and a butt joint, and then the changes in bending strength were compared on wood samples from beech, oak, ash and maple after thirty cycles of an intensive washing process using cleaning tablets and subsequent acclimatization of the samples. These were compared with samples that did not undergo the cleaning process.
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Posouzení zdravotního stavu a dendrometrických charakteristik Kočárové aleje, Frýdlant
Soukup, Vojtěch
ABSTRACT The assessment of health condition and dendrometric characteristics in Kočárová alej (Carriage alley) in Raspenava. The aim of this work is the assessment of health condition of an alley in Raspenava, the detection of main insect pests and tree diseases and a subsequent comparison with the assessment of relicts of felling of this alley. Trees planted along roads by our ancestors are integral parts of our landscape. Carriage alleys were in the past planted in particular for an improvement of the transport of carriages. However, the development of transport caused that alleys are currently considered to be obstacle or hazardous to still increasing automobile transport. This problem is in extreme cases solved through felling of old trees and their replacement with a new planting pursuant to valid standards concerning the distance of trees planted along communications. However it often results in breach of planned compensatory planting due to an excessive interference with plots neighbouring with the communication. The aim of this work is the assessment of the necessity of performed intervention in relation to the health condition of trees.
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Sledování biologie Hymenoscyphus fraxineus - nekrózy jasanů na základě odchytu spór
Kasal, Vojtěch
My bachelor thesis deals with an ash dieback which is caused by a pathogen called Hymenoscyphus fraxineus. This thesis deals with the evaluation of climate conditions in comparison with the occurrence of spores of the pathogen. The practical part of the thesis is based on air sampling at the research area in the Hackerova školka. Data were collected with air sampler of burkard´s type. Processing of collected samples followed in laboratory. Data were then analyzed.
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Návrh židle
Jonáš, Martin
This diploma thesis describes the design and manufacture of a chair prototype made of solid wood. In the creation of the design of this chair, knowledge of the typology, furniture construction, ergonomics, anthropometry and materials are mentioned in the theoretical part. The practical part is made with the acquired knowledge of 3D visualizations and technical documentation. By using these documents a prototype of a chair was made in scale 1:1.
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Monitoring rozšíření nekrózy jasanů (Hymenoscyphus fraxineus) v lesních porostech severní Moravy
Fuchs, Ladislav
This bachelor thesis deals with fungual pathogen H. fraxineus. This pathogen is spread troughout all Europe and attacks the ashes. There is no place in the Czech Republic where the ash will not be attacked. The work should help solve the problem called Hymenoscyphus fraxineus. The aim is investigate all the factors infuencing the intensity od infection in stands. In thesis has been found that most of abiotic growth factors have no effect on ash cultivation. The effect od the health of ash is positiveli reflected when the ash grown on natural habitats i fit has been naturally picked in the stand and is the as his mixed randomly
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Monitoring houbových organismů podílejících se na rozkladu bází kmenů jasanů (Fraxinus excelsior) napadených nekrózou jasanu Hymenoscyphus fraxineus
Slezáková, Hana
This thesis deals with the monitoring of fungal organisms involved in the decay of bases of common ash trees (Fraxinus excelsior) affected by the ash dieback (Hymenoscyphus fraxineus) infection. Monitoring was carried out in winter 2018 on 50 trees. Samples were taken from tree bases and sorted into 5 health categories. The total area of samples and the area affected by rot was measured in a laboratory. Fungal organisms were isolated from infected and healthy wood and identified by DNA extraction and sequencing. Finally, the determined species were statistically evaluated by a combination of constrained and unconstrained ordination methods. In total 436 pure cultures of fungal organisms were isolated. 23 species of fungal organisms were determined, of which 21 were in symptomatic wood (with a visible rot) and 5 in asymptomatic (healthy) wood. Xylaria polymorpha was confirmed to be present in most trees, it was found in 27 samples - 16× in asymptomatic wood and 11× in symptomatic wood. Hymenoscyphus fraxineus was isolated once from the 1st health category and once from the 5th health category from symptomatic wood.
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Mortalitní faktory provázející odumurání jasanů v důsledku infekce nekrózou jasanů Hymenoscyphus fraxineus v oblasti podhůří Orlických hor.
Vágner, Filip
This bachelor thesis deals with necrosis of ash caused by pathogenic fungus Chalara fraxinea. The work contains summarized informations about phenology, bionomy and charakteristic symptoms which were used during the practical research. Next part of the thesis -- the practical research itself -- is focused on charting of intensity and spreading direction of the disease in one specific forest section. In this part are also mentioned possible factors, which could modify (accelerate or restrict) the growth of the fungus in specific cases. Than, in the last part, are walorized financial damages caused by this pathogenic fungus and suggested some interventions, which can contribute to survival of ashes in the forests.
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Jídelní stůl z masivního dřeva
Svojšová, Iveta
The reason why this thesis was crated is that the author was asked to design this table according the needs of investors and also asked to provide the manufacturing process. That lead to the construction design and final production of the table. Author then could be present in the whole realization process. The table was crated with respect for nature, craft and personal approach to the entire implementation.
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