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Biochemical aspect of investigation of the natural-origin binders and varnishes in the paint layer of old paintings
Pecháčková, Soňa ; Kubíčková, Božena (referee) ; Hudeček, Jiří (advisor)
The subject of this work are choosen bioanalytical methods, used for the identification of organic binders and varnishes in coloured layer of ancient paintings. In the past, the plant and animal substances were used as a binders and varnishes. To those materials belong proteins, oils, polysacharide gums and resins. Succesful analysis in the history of using binders and varnishes demands a good knowledge of their chemical qualities and reactivity during the process of aging. Nowadays are prefered the methods and technics, which don?t destruct the sample and which are non-invasive towards the whole artwork. Recently, the imunofluorescence technics have been started to use as the alternative methods of classical and easier microchemical tests. The spectroscopic methods are widely used in material investigation of ancient artworks. The main is infrared spectometry (FTIR) and Raman spectroscopy. The methods of nuclear magnetic resonance are significant mainly for studying changes of connective and isolating material during the process of aging. To indentify mainly protein binders, the technic of mass spectrometry (MALDI-TOF) is widely used. Due to the progress of technic the paper and thin-layer chromatography were replaced by very effective high performance liquid chromatography (HPLC), gas chromatography (GC)...
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Rheological properties of building binders in their fresh state
Hegrová, Michaela ; Rovnaník, Pavel (referee) ; Vyšvařil, Martin (advisor)
This thesis is devoted to the rheological properties of building binders. The theoretical part focuses on individual types of building binders, their rheological properties and basic parameters determinated during the rheological characterization of building binders. The practical part deals with the resultes obtained from the meansurements on a rotational rheometr using the geometry type of plate to plate. These results are subsequently evaluated.
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Research in the Field of Anhydrite Binders
Břicháčková, Jana ; Smetanová, Lenka (referee) ; Gazdič, Dominik (advisor)
The presented work deals with research in the field of sulfate binders on the anhydrite base. Conceptually, it is divided into a general theory of sulfate binders and anhydrite mortar compounds, which is describing in detail the using of anhydrite mortar compounds on the poured floor screeds, and then the experimental part, where is made the mineralogical analysis of seven different gypsum resources and subsequent is monitored the effect of two sulfate exciters on the achieved technological properties and hydration process.
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Preparation of hystorical geopolymers
Šrámková, Eva ; Šoukal, František (referee) ; Havlica, Jaromír (advisor)
Diploma thesis studies historical bonding agents on the base of geopolymers. The aim of the thesis is to find a proper material composition, especially made of natural clay materials (kaolinite, bentinite) and their modifications (metakaoline). These bonding agents have to have a suitable type of an activator that guarantees good bonding properties. Therefore testing of various kinds of alkaline activating ingredients on the same mineral composition was done. Except of usual hydroxides and a water glass, ancient natrons (mixtures of alkaline carbonate with addition of appropriate chlorides) and a lime mash were used as the activators. From the above mentioned mixtures, series of samples (columns 20 x 20 x 100 mm) stored at the laboratory temperature were prepared. In the prepared mashes, their workableness and moulding were investigated. In the developed samples, their surface appearance was observed together with a number of efflorescence and its types. An indivisible part of the research was formed by determination of mechanical properties of the experimental columns such as a compressive strength and a tensile strength in bending. Furthermore, phase composition of the samples and its changes with a temperature increase were investigated. For these tests, XRD and TG – DTA methods were used. A multi-seat isoperbolic calorimeter was used to study hydratation that was also the important part of the general evaluation of designed mixtures.
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Surface treatment by wet paiting
Fical, Karel ; Žák, Ladislav (referee) ; Kubíček, Jaroslav (advisor)
Protection of various coating materials is today very important, both in terms of aesthetic, functional and, especially corrosion. Corrosion annually causes significant damage to metal structures and degradation of material can cause a total damage of the parts or the whole structure. When appropriate choice of coating materials can suppress the corrosion and its manifestations delay up to several years. Today, the protection of organic material coats the most common way and takes 80 to 90% of all coatings. When selecting paints and their subsequent applications we care about the material properties of the edit, its functional use, the environment in which they will be located and the properties of paint itself. To achieve satisfactory properties, it is necessary to create a technological process for the specific case.
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Study of anhydrite binder
Břicháčková, Jana ; Fridrichová,, Marcela (referee) ; Gazdič, Dominik (advisor)
The present work deals with research in the preparation of sulphate anhydrite binders based. It is conceptually divided into a general theory of sulphate anhydrite binders and binders, focusing in particular anhydrite cast floors, as well as search anhydrite binders of research training at the Institute of THD and study requirements for screed materials, with emphasis on anhydrite screed mix.
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Binders for pellets from biomass
BARTOŠ, Pavel
Pellets from biomass represent an appropriate form of biofuel for combustion. They are characterized by good fuel parameters, they enable efficient storage, transport and handling, and automatic fuel supply to the combustion chamber. Pellet production is quite a complicated and energy-consuming process. During the production it is necessary to ensure that the amount of input energy was the same or even smaller than the energy obtained. To streamline the production and improve thermo-mechanical properties some binders and additives can be used. It is possible to increase the strength, density, calorific value and resistance to abrasion by using such binders and additives, in addition, you may achieve changes in characteristics and quantity of ash, decrease of the cost of pellets production, the use of materials which are separately difficult to burn and not easy to process by pelleting and affecting emission parameters during combustion. The most important binders and additives with a positive effect on pellets include: lignin, starch, molasses, glycerol, paraffin and palmitin, carboxymethyl cellulose, limestone, rye and corn flour, lignosulfonate and waste potatoes.
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