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Plasters and mortars from the theatre in Nea Paphos (Cyprus): A multidisciplinary study
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Experimental study of Palaeozoic limestones of the Barrandian and their possible use for burning of hydraulic limes and natural cement
Full text link54 Summary In this experimental study, selected Devonian limestones of the Prague Basin (i.e. samples from the historic quarry of Branické skály) were examined to find their suitability for production of hydraulic limes or for natural cement. Four representative samples of the dvorecko-prokopské limestone were sampled in the form of blocks weighing approximately 10 kg each, from the layer of the quarry wall that had been chosen based on literature research. A detailed mineralogical-petrographic examination of samples was the first step, in an attempt to obtain their mineralogical composition, microstructure and texture. Samples were analysed by polarizing microscopy and cathodoluminescence of thin sections, and X-ray diffraction of insoluble residues determined by treatment with both the hydrochloric acid and the acetic acid solution. Mineralogical composition of the insoluble residuals was illite, kaolinite, quartz and Na-plagioclase (albite). Two samples contained among above mentioned mineral phases also chlorite. The utility of studied limestones for the production of hydraulic binders (hydraulic limes and natural cement) was derived from both the calculations based on obtained chemical analyses (included standard cement and lime indexes and modules) and the firing experiments. The firing experiments..
Limestones of Český kras and their use for hydraulic limes and natural cements
No full textii Summary This bachelor thesis is focused on the possible use of limestones from the Český kras area for the preparation of alternative inorganic binders, namely for hydraulic limes and natural cements. In the introductory chapters, the geology of Český kras is described. Silurian and Devonian beds make the most important lithostratigraphic members. Then, the history of limestone exploitation and processing is explained. It is followed by the petrographical characteristic of limestone - its mineralogical and chemical composition, the structure and the texture, the classification, the genesis and the diagenesis. Major part of the thesis focuses on inorganic binders - their basic characterization and evaluation. Limestones are discussed from the point of their general use in the industry. The limestones from the Český kras area are analyzed based on their chemical composition (based on the previously reported data) and evaluated for the potential use for burning of hydraulic limes and natural cements
Experimental study of Palaeozoic limestones of the Barrandian and their possible use for burning of hydraulic limes and natural cement
No full text54 Summary In this experimental study, selected Devonian limestones of the Prague Basin (i.e. samples from the historic quarry of Branické skály) were examined to find their suitability for production of hydraulic limes or for natural cement. Four representative samples of the dvorecko-prokopské limestone were sampled in the form of blocks weighing approximately 10 kg each, from the layer of the quarry wall that had been chosen based on literature research. A detailed mineralogical-petrographic examination of samples was the first step, in an attempt to obtain their mineralogical composition, microstructure and texture. Samples were analysed by polarizing microscopy and cathodoluminescence of thin sections, and X-ray diffraction of insoluble residues determined by treatment with both the hydrochloric acid and the acetic acid solution. Mineralogical composition of the insoluble residuals was illite, kaolinite, quartz and Na-plagioclase (albite). Two samples contained among above mentioned mineral phases also chlorite. The utility of studied limestones for the production of hydraulic binders (hydraulic limes and natural cement) was derived from both the calculations based on obtained chemical analyses (included standard cement and lime indexes and modules) and the firing experiments. The firing experiments..
Influence of the mineralogical composition of raw material on phases formed during the burning of hydraulic lime and natural cement
Full text linkNatural hydraulic lime and natural cement have been used in the building industry for centuries. These inorganic hydraulic binders are called "traditional" or "alternative" because they can, in some cases, substitute modern Portland cement. The recent increased interest in these binders is due not only to their use in restoration practices, but also because their production and use is less energetically demanding than in modern cements. Historically, many types of hydraulic binders were produced in the regions of Bohemia and Moravia. However, much information has been lost about their manufacturing process, which raw materials were used, and we are uncertain of the exact character and properties of the burned material. To date, studies have only addressed the impact of the chemical composition of raw material on the parameters of the burned material - all this is well known for Portland cement, much less for other types of hydraulic binders. The aim of this dissertation was to study the various types of raw materials (limestone containing non- carbon admixtures) and to understand the characteristics of their respective hydraulic lime and natural cement. This was done by analyzing the impact of conditions (highest achieved burning temperature and time of burning) and the mineral and chemical..
Survey of the connection of the stone elements in „archingʺ of the battlement of the Powder Tower in Prague
No full textSurvey of the connection of the stone elements of the Powder Tower in Prague using ground penetrating radar. The aim is to verify the existence of connecting elements with the „archingʺ of the battlements and side supports. Interpretation of the radargrams points to a stonemasonry dowels. The mortar contains an iron admixture
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Limestones of Český kras and their use for hydraulic limes and natural cements
No full textii Summary This bachelor thesis is focused on the possible use of limestones from the Český kras area for the preparation of alternative inorganic binders, namely for hydraulic limes and natural cements. In the introductory chapters, the geology of Český kras is described. Silurian and Devonian beds make the most important lithostratigraphic members. Then, the history of limestone exploitation and processing is explained. It is followed by the petrographical characteristic of limestone - its mineralogical and chemical composition, the structure and the texture, the classification, the genesis and the diagenesis. Major part of the thesis focuses on inorganic binders - their basic characterization and evaluation. Limestones are discussed from the point of their general use in the industry. The limestones from the Český kras area are analyzed based on their chemical composition (based on the previously reported data) and evaluated for the potential use for burning of hydraulic limes and natural cements
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