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Optimization of chemical analysis of selected components in material of historical artworks
Pekař, Martin ; Čabala, Radomír (advisor) ; Hudeček, Jiří (referee)
The simplification of the historical pieces of work samples' treatment is described in the dissertation. The recent methods have been inappropriate therefore, modification of the treatment was necessary. The dammar and copal resin, important restoration materials, were used in the experiment. HPLC-MS, HPLC-ELSD, GC-FID, GC-MS and pyrolysis GC- MS were applied. The concentration of fatty acids in the historical sculpture was determined by GC-MS, and it was compared to the content of fatty acids inside an egg. For identification of monosaccharide in the gum, GC-MS (hexamethyldisilazan, trimethylchlorsilan, and pyridine) is the suitable method. GC-MS determines the same composition of dammar resin as stated in the cited sources. The simple process for the samples' treatment was designed.
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Biochemical Aspects of Artwork Restoring
Boledovičová, Petra ; Hudeček, Jiří (advisor) ; Kubíčková, Božena (referee)
The following bachelor thesis is focussed on findings on the field of art restoring in connection with its biochemical aspects. In itroduction is resumed brief history of art restoring and generally defined terms of preservation, restoring, art and paint. For better understanding basic paint techniques (aquarelle, gouache, tempera and oil painting), strata sequence and instruments and materials commonly used for art work are mentioned. Most frequently used organic and inorganic pigments are briefly mentioned, however this thesis is mainly focussed on applied organic compounds - lipids, proteins, polysacharides and terpenoids - its composition, characteristics, usagea nd possible interactions. The following thesis is written in czech. Key words: restoring, art work, paint, organic binders, lipids, proteins, polysacharides, terpenoids
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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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Use of special binders for recycling of asphalt mixtures at mixing plants
Pěch, Pavel ; Špaček, Petr (referee) ; Varaus, Michal (advisor)
The thesis deals with the matter of usage of special asphalt binders for production of asphalt mixtures containing recycled materials in asphalt plant. For comparison analysis of characteristics of special binder used in roads is necessary to compose different mixtures of asphalt – one with binder containing R-materials, and another benchmark mixture with binder used in common mixtures without recycled materials. Investigation of features of mixtures with different binders is carried out by selected performance tests of asphalt mixtures. Evaluation and comparison of the results is described in the final section of the thesis.
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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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