Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
Browse
3 results
Search Results
Now showing 1 - 3 of 3
Article Citation - WoS: 14Citation - Scopus: 17The Effects of Natural Zeolite and Silane Coupling Agents on Melting and Crystallization Behaviour of Polypropylene(Springer Verlag, 2008) Başalp, Dildare; Tıhmınlıoğlu, FundaThe thermal characterization of polypropylene (PP) composites containing untreated and treated zeolite with different silane coupling agents was carried out using thermogravimetric analysis (TG) and differential scanning calorimetry (DSC) to investigate the effects of natural zeolite and surface modifiers on melting, crystallization and degradation behaviour of PP. 3- aminopropyltriethoxysilane (AMPTES), methyltriethoxysilane (MTES) and 3-mercaptopropyltrimethoxysilane (MPTMS) were used as surface modifiers at four different concentrations (0.5-2.0 mass%). Thermal analyses indicated that silane treatment and 2-6 mass% zeolite addition have no significant effect on the melting and degradation temperatures of the composites. The crystallization temperatures of the composites were increased due to the nucleating effect of the zeolite. The influence of the modifiers on the interactions between PP and zeolite was determined by the activities of untreated and treated zeolite. The maximum interactions leading to good adhesion were observed in the AMPTES treated composites. Also, non-isothermal crystallization kinetics of the composites was analyzed using Avrami and Kissinger models.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.Article Citation - WoS: 38Citation - Scopus: 43Degradation Kinetics of Anthocyanins From Sour Cherry, Pomegranate, and Strawberry Juices by Hydrogen Peroxide(John Wiley and Sons Inc., 2002) Özkan, Mehmet; Yemenicioğlu, Ahmet; Asefi, N.; Cemeroglu, BekirDegradations were studied at different hydrogen peroxide (H2O2] concentrations (9.31 to 27.92 mmol. L-1] over a range of 10 ° to 30 °C. Degradation of anthocyanins by H2O2 was described by first-order function. Comparison of t1/2 values revealed that sour cherry anthocyanins were the most resistant to H2O2, followed by pomegranate and strawberry anthocyanins. Thus, the removal of residual H2O2 from the juice contact surfaces of aseptically packaged strawberry juices should be controlled more carefully to prevent anthocyanin degradation. Respective Ea values were between 9.4 to 11.1, 9.5 to 11.4, and 11.4 to 12.2 kcal.mol-1; and Q10 values between 1.59 to 2.22, 1.62 to 2.05, and 1.76 to 2.36 for strawberry, sour cherry, and pomegranate anthocyanins.