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Objective: The purpose of this study is to evaluate the bond strength of different repair systems by using composite resin and ceramic cementation repair methods to zirconia-based ceramics. Material and Method: All-ceramic blocks (IPS Empress II; Ivoclar Vivadent, Schaan, Liechtenstein) sized 4.00 mm in length, 5.4 mm in width, and 3.00 mm in height were fabricated by dental laboratory as thirty specimens. CAD/CAM zirconia blocks (n =40) (Prozir; SeramDent, Turkey) sized 5.00 mm in length, 5.4 mm in width and 13.0 mm in height by CEREC System were fabricated from fully sintered Y-TZP core. Zirconia specimens were randomly divided into seven groups for the following different intraoral repair systems(Clearfil, Cimara Zircon, Bisco) and a control group. Every ten specimens were repaired as same sized. Control group was fabricated by conventional firing as unbroken solid zirconia ceramic samples. Each specimen underwent 5000 cycles of thermocycling. The SBSt (Shear bond strength test) was performed by loading force on the repaired piece to record load-to-failure. Failure mode was evaluated using a digital microscope and SEM. SBSt data were analyzed using one-way ANOVA and Tukey’s HSD test. Results: Clearfil and Cimara Zircon systems significantly increased the bond strength for composite resin method when compared with the Bisco system (respectively p <0.001, p =0.001). All-ceramic method significantly increased the bond strength when compared with the composite resin in Bisco system (p <0.001). Conclusion: Although the composite restoration method is effective for repair, the all-ceramic/zirconia repair method can be an option for repairing layered zirconia restorations. [ABSTRACT FROM AUTHOR]

In this study, pollen morphology of some endemic species belonging to Scrophulariaceae family and their distribution limited to Erzincan was studied by using Scanning Electron Microscope (SEM). Pollen sizes, pollen types, pollen patterns, polen ornaments and apertures tructures of Scrophularia erzincanica, Scrophularia fatmae, Verbascum leiocarpum, Verbascum ozturkii were investigated. In both Scrophularia species pollen size is medium and polen types tricolpat. Although pollen form of two species is close to each other, Scrophularia erzincanica was found to be subprolate and in Scrophularia fatmae it was perprolate. Ornamentations were determined as verrucat and reticulat respectively. In the study of Verbascum species; In the two types studied, it was found that the pollen size was medium-sized, the pollen shape was spherodial in Verbascum leiocarpum, the subprolate was Verbascum ozturkii, the polen types were tricolpate and their ornamentations were reticulate. When the findings of the studied species are evaluated, it is thought that polen morphologies in Scrophularia speciesare not enough to be used in the differentiation of taxa, and Verbascum species shows differences in polen type and it can be used in distinguishing taxa in this context. [ABSTRACT FROM AUTHOR]

Undoped and Erbium (Er) doped zinc oxide (ZnO) films were prepared on p-Si substrates by sol gel method using spin coating technique. The effect of Er dopant on the structural, morphological and optical properties of ZnO film was investigated by X-ray diffractometer, scanning electron microscope (SEM) and UV-vis spectrophotometer, respectively. From X-ray diffraction (XRD) spectra, the films were crystallized in hexagonal wurtzite structure in zincite phase. The structural parameters such as grain size, dislocation density, lattice parameters, strain and stress were calculated. From the SEM images, it is seen that the film surfaces are well-coated, uniform, without cracks and pores. ImageJ program was used to investigate the average particle size, grain boundaries and the surface of the films. The optical properties were studied by diffuse reflectance spectra measured by UV-vis spectrophotometer and the optical band gap values were determined by differential reflectance and Kubelka-Munk theory. In both methods, it was determined the optical band gap value of ZnO film increases or decreases irregularly with the Er content. It was observed that the optical band gap of the 0.4% Er doped ZnO film was larger than the other films. [ABSTRACT FROM AUTHOR]

In this study, diaza-crown ether and phosphaze-crown ethers have been investigated in scanning electron microscope (SEM) and compared to their electron micrographs. In analysis of micrograph have been observed that compounds has different morphological structure [ABSTRACT FROM AUTHOR]

In this research. Cyclotella comta from Bacillariophyta division (in samples which received from surroundings Tokat-Turkey) have been cultured in culture medium and investigated in scanning electron microscope (SEM). At study have been detailed C. comta in point of ultrastructurel. In analysis of micrograph have been observed that frustule has different morphological structure [ABSTRACT FROM AUTHOR]

In this research, Nitzschia palea from Bacillariophyta division (in samples which received from surroundings Tokat-Turkey) have been cultured in culture medium and investigated in scanning electron microscope (SEM). In analysis of micrograph have been observed that polar nodule has different morphological structure. [ABSTRACT FROM AUTHOR]

In this study, cyclic oxidation tests were conducted on C-276 Ni alloy samples both at low (T<1000 °C) and high temperatures (T>1000 °C) in stagnant air environments. After the tests, planar and cross-sectional structural features of the scales as well as the chemical compositions of the metallic and oxide regions were investigated using a scanning electron microscope equipped with a backscattered electron detector and a x-ray energy dispersive spectrometer (EDS). Results of the point, line and area EDS analyses were used to explain the oxidation behavior of the alloy. Both relatively higher weight gains and volatilization of Molybdenum (Mo) were observed for the samples oxidized at temperatures above 1000 °C. Results suggested that Mo volatilization might be responsible for the scale spallation observed for the samples oxidized at higher temperatures. [ABSTRACT FROM AUTHOR]