Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

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Now showing 1 - 6 of 6
  • Article
    Citation - WoS: 21
    Citation - Scopus: 23
    Determination of Caco 3 and Sio 2 Content in the Binders of Historic Lime Mortars
    (Springer Verlag, 2012) Uğurlu Sağın, Elif; Böke, Hasan; Aras, Nadir; Yalçın, Şerife
    The binders of historic mortars composed of small grain sized silica (SiO 2) and carbonated lime (CaCO 3) are considered as the main part that give hydraulic character and high strength to the mortar. In this study, FTIR, SEM-EDS, LIBS and XRD spectroscopy were used to find out the weight ratios of CaCO 3 to SiO 2 in the binders of historic lime mortars. For this purpose, a series of pure calcium carbonate and silica mixture were prepared in ten combinations in varying ratios from 0.5 to 5. Calibration curve was prepared for each analysis by plotting the peak area or intensity ratios of CaCO 3 to SiO 2 versus the weight ratios of CaCO 3 to SiO 2. A good linear correlation coefficient was obtained for each analysis respectively. The analyses were then tested on the binder of the Roman mortar samples. The results indicated that FTIR, SEM-EDS and LIBS spectroscopy are convenient tools to determine the weight ratios of CaCO 3 to SiO 2 in the binders of mortars. But XRD spectroscopy is not convenient for quantitative analysis of binders due to the presence of varied amounts of amorphous or poor crystalline silica in their compositions.
  • Article
    Citation - WoS: 28
    Citation - Scopus: 29
    Characteristics of Bricks Used in the Domes of Some Historic Bath Buildings
    (Elsevier Ltd., 2013) Uğurlu Sağın, Elif; Böke, Hasan
    In this study, characteristics of bricks used in the domes of some historic bath buildings dated to 15th century in Izmir were determined in order to indicate the properties of repair bricks that will be used in the conservation works of the domes. For this purpose, their basic physical properties, elemental and mineralogical compositions, firing temperatures and microstructural properties were determined by using XRF, XRD, SEM-EDS and TGA analysis. Analysis results indicated that the bricks are of low density, high porosity and were produced from raw materials containing low amounts of calcium poor clays fired at low temperatures (<. 900. °C). They are mainly consisted of small pores with r<. 5. μm that make the bricks more susceptible to salt crystallization and freeze-thaw cycles. Although the bricks were fired at low temperatures and susceptible to salt crystallization and freeze thaw cycles, the structural systems of the domes remained without losing their integrity due to the moderate climatic conditions of Izmir. Repair bricks that will be used in the conservation works of the domes should be compatible with the original ones and produced from calcium poor clays by firing at low temperatures.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 10
    Construction Techniques of Domes in Some Ottoman Baths
    (Elsevier Ltd., 2013) Reyhan, Kader; İpekoğlu, Başak; Böke, Hasan
    In Ottoman bath architecture, the dome is the spherical structural component covering the square planned dressing hall, warm and hot spaces. In this study, the relationship between bond type, dome span, dome height, dome thickness, and the number of oculi of domes in some Ottoman baths located in Western Anatolia (Turkey) were investigated for the purpose of evaluating construction techniques and architectural characteristics. The studied domes were constructed with brick and lime mortar as binder. In the construction of domes, whole and half bricks with different dimensions were used. In all domes, the surfaces were covered with brick-lime plaster, a thin layer on the interior and a thick layer on the exterior. Terracotta pipes placed in the brick bond or the openings made through the brick bond constituted oculi for lighting. Depending on the brick bond, a linear relationship was determined between the span, height, and number of oculi, whereas a mathematical ratio between 1:10 and 1:12 was determined between the span and thickness of the domes. It has also been noted that as the dome span increases, so does the height, thickness at the springing level and the number of oculi. The domes examined with these properties should be seen as historical documents representing the construction technology of the 15th century. Therefore, these properties of domes must be preserved and special care needs to be taken as not to lose the original qualities of these domes during conservation works.
  • Article
    Citation - WoS: 10
    Citation - Scopus: 12
    Weathering of Andesite Monuments in Archaeological Sites
    (Elsevier Ltd., 2013) Kaplan, Çaglayan Deniz; Mürtezaoğlu, Fulya; İpekoğlu, Başak; Böke, Hasan
    Archaeological sites, which are the integral parts of cultural heritage, have to be conserved as a whole to have a variety of information about past societies. In this study, the weathering problems of unburied and newly excavated andesite monuments in Aigai archaeological site (Manisa, Turkey) were investigated for the purpose of their conservation. With this intent, the basic physical properties, mineralogical and chemical compositions and microstructural properties of sound and weathered samples were determined by using XRD, SEM-EDS, FT-IR and TGA analysis. Results of the study indicated that the weathering mechanisms of unburied and post-excavated andesite differ from each other. The main weathering problems observed on the unburied stones are mainly increasing microcracks from inner parts to the surfaces, deposition of iron oxides and microbiological colonization due to climatic conditions of the site. In the newly excavated areas, calcium carbonate deposition, accumulation of clay minerals and microbiological colonization are the main weathering problems due to weathering of silica minerals through the action of carbon dioxide and water during burial.
  • Article
    Citation - WoS: 121
    Citation - Scopus: 136
    Quantification of Caco3-Caso3·0.5h 2o-Caso4·2h2o Mixtures by Ftir Analysis and Its Ann Model
    (Elsevier Ltd., 2004) Böke, Hasan; Akkurt, Sedat; Özdemir, Serhan; Göktürk, E. Hale; Caner Saltık, Emine N.
    A new quantitative analysis method for mixtures of calcium carbonate (CaCO3), calcium sulphite hemihydrate (CaSO 3·1/2H2O) and gypsum (CaSO 4·2H2O) by FTIR spectroscopy is developed. The method involves the FTIR analysis of powder mixtures of several compositions on KBr disc specimens. Intensities of the resulting absorbance peaks for CaCO 3, CaSO3·1/2H2O and CaSO 4·2H2O at 1453, 980, 1146 cm-1 were used as input data for an artificial neural network (ANN) model, the output being the weight percent compositions of the mixtures. The training and testing data were randomly separated from the complete original data set. Testing of the model was done with successfully low-average error levels. The utility of the model is in the potential ability to use FTIR spectrum to predict the proportions of the three substances in unknown mixtures.
  • Article
    Citation - WoS: 22
    Citation - Scopus: 23
    Effect of Some Surfactants on So2-Marble Reaction
    (Elsevier Ltd., 2002) Böke, Hasan; Göktürk, E. Hale; Caner Saltık, Emine N.
    In the polluted atmosphere, sulphur dioxide (SO2) reacts with calcite (CaCO3) in marble producing calcium sulphite hemihydrate (CaSO3·0.5 H2O) and gypsum (CaSO4·2H2O). Gypsum develops crust at rain-sheltered surfaces and then, being more soluble, accelerates erosion at areas exposed to rain. Eventually, all these lead to significant deformations in the appearance and structure of marble surfaces. Clearly, some precautions must be taken to stop or at least to slow down this deterioration process which destroys our cultural heritage. In this study, we have investigated the possibilities of preventing the SO2-marble reaction by using water-soluble surfactants: Abil Quat 3270 and Tween 20. Experiments for measuring their effects have been carried out at conditions simulating the dry deposition of SO2. Infrared spectrometry and scanning electron microscopy were used to analyze the mineralogical composition and morphology of the reaction products. The extent of sulphation reaction was calculated by determining calcium sulphite hemihydrate and gypsum quantitatively by an IR approach and also by weight increases observed during the progress of SO2-marble reaction. A 10% decrease is observed in the total sulphation with both surfactant applications. The results have been discussed in relation to the possible stages of sulphation reaction and surface reactions of calcite.