Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Citation - WoS: 34Citation - Scopus: 37Humidity Adsorption Kinetics of Water Soluble Calix[4]arene Derivatives Measured Using Qcm Technique(Elsevier Ltd., 2010) Okur, Salih; Kuş, Mahmut; Özel, Faruk; Yılmaz, MustafaWe report on the optimization and characterization of water soluble calix[4]arene derivative as a humidity sensor based on quartz crystal microbalance technique. The moisture adsorption and desorption kinetics of calix[4]arene were investigated. The Langmuir model was used to determine the kinetic parameters such as adsorption, desorption rates and Gibbs free energy between relative humidity between 29% and 78%. Reproducible experimental results were obtained showing that water soluble calix[4]arene films have a great potential for humidity sensing applications at room temperature operations. © 2009 Elsevier B.V. All rights reserved.Article Citation - WoS: 36Citation - Scopus: 30Humidity Adsorption Kinetics of Calix[4]arene Derivatives Measured Using Qcm Technique(Elsevier Ltd., 2010) Okur, Salih; Kuş, Mahmut; Özel, Faruk; Aybek, Vildan; Yılmaz, MustafaThis study focuses on the characterization of sulphonated calix[4]arene derivative films coated on a quartz substrate with a thickness of 40 nm by spin coating method for humidity detection. The humidity adsorption kinetics of the sulphonated calix[4]arene films was investigated by quartz crystal microbalance (QCM) technique. The Langmuir model was used to determine the adsorption rates and Gibbs free energy for various relative humidities between 11% and 97%. Our reproducible experimental results show that suphonated calix[4]arene films have a great potential for humidity sensing applications at room temperature operations. © 2009 Elsevier B.V. All rights reserved.Article Citation - WoS: 141Citation - Scopus: 154Electrical Characterization of Pedot: Pss Beyond Humidity Saturation(Elsevier Ltd., 2009) Kuş, Mahmut; Okur, SalihPEDOT:PSS humidity sensor was fabricated using a drop-casting method between thermally evaporated gold electrodes with 30 μm separation and 300 μm channel width on a glass substrate. AC, DC resistivity, and AFM techniques were used to characterize the PEDOT:PSS humidity sensor in the same environmental conditions. The change of resistivity was monitored with increasing relative humidity (RH) up to 90%. The resistivity increases linearly up to a maximum value, and then it starts to decrease abruptly above 80% relative humidity (RH) after saturation of water uptake. The decrease in resistivity above 80% RH seems to be due to the water meniscus layer formed on the saturated PEDOT:PSS film. Below 80% RH, the device works like a humidity sensor.Article Citation - WoS: 44Citation - Scopus: 44Ettringite Formation in Historic Bath Brick-Lime Plasters(Elsevier Ltd., 2003) Böke, Hasan; Akkurt, SedatTwo types of historic hydraulic brick-lime plasters from a selected Ottoman bath are examined to characterize their technology and the appropriateness of their use in bath. The first type of plaster is original and structurally sound, while the historic repair plaster is the second type and is found to have deteriorated despite being exposed to the same environment. This difference is investigated by comparing their raw material compositions and the pozzolanic activities of the brick powders used in the plasters. Although these results showed no significant differences, ettringite crystals are detected in the historic repair ones by XRD, FTIR, and SEM-EDS analysis. The repair plaster may have lost its integrity owing to the expansion generated by the growth of ettringite crystals in the plaster. In this study, the ettringite formation is discussed in relation to hydration reaction products of lime-brick plasters, possible sources of gypsum, and the climatic conditions of historic bath building.