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In this study, an electrochemical sensor based on carbon nanotube immobilized with diester-functionalized calix[4]arene (CNT-Calix-DE) was developed to determine the ondansetron content in pharmaceutical preparations. During the sensor preparation stage, the glassy carbon electrode surface was modified with CNT-Calix-DE. The surface morphology, electrochemical characterization and analytical performance of the sensor were examined using scanning electron microscope (SEM), electrochemical impedance spectroscopy (EIS) and differential pulse anodic stripping voltammetry (DPASV). Under optimal experimental conditions, the developed sensor showed a linear response to ondansetron in the concentration range of 1.0-10.0 M. Analytical applicability of the sensor was investigated by determination of ondansetron in pharmaceutical preparations. [ABSTRACT FROM AUTHOR]

In the study, the micromorphology of labellum in samples belonging to 10 different Ophrys taxa was examined by Scanning Electron Microscopy (SEM) method and the results were presented in comparative tables. While the samples were collected from the field, they were taken to 70% alcohol, some of them were dried according to the herbarium rules and identified. The labellum samples extracted from alcohol were dissected under the stereomicroscope with scalpel and needles and placed directly into the iron apparatus of the SEM device with double-sided adhesive tapes. These samples, whose alcohol was completely evaporated by waiting for one night, were examined directly with Scanning Electron Microscope (SEM) and labellum microphotographs were taken. According to our findings, it was determined that the speculum structures are very different from each other, and the shape and distribution of the hair / papilla in the basal, median and lateral regions differ from species to species.It was also determined that the apex region differs in O. fusca, O. lutea, O. speculum, O. mammosa, O. pseudomammosa, O. heldreichii, O. umbilicata, and O. holoserica species. In summary; It was concluded that the labellum speculum and apex structure of the 1st degree and the basal, median and lateral region surface characteristics of the 2nd degree differ widely between the species. [ABSTRACT FROM AUTHOR]

Nowadays, higher performance expectations from turbines and internal combustion engines, rapid extinction of fossil fuels, global warming and increasingly tighter emission standards worldwide are the biggest problem of engine manufacturers. The most important solution approach for this problem is the coating of metallic parts of turbine blades and/or combustion chamber with a thermal barrier coating material having low thermal conductivity. This solution leads to significant improvements in engine performance and efficiency. On the other hand, rare element doped new generation ceramic thermal barrier coating material materials having low thermal conductivity have attracted considerable attention in recent years. In this study, the metallic bond layers have coated on the metallic substrates by using high-speed oxy-fuel spraying method and then La2Zr2O7 based ceramic top layers have coated as double layered by using atmospheric plasma spraying method. In the scanning electron microscope analyses, it was found that the thicknesses of the ceramic top layers ranging from 375 to 480 μm and the porosity values were among 10.2 and 12.5%. Moreover, the interfaces between the layers were continuous and there was no metallographically problem. Therefore, it is understood that, La2Zr2O7 based ceramics were successfully coated. In addition, X-ray diffraction analysis revealed that there was no phase transformation or chemical degradation after atmospheric plasma spray process. [ABSTRACT FROM AUTHOR]

In this work, rice husk and burned rice husk were used as low cost adsorbents to remove a cationic dye, Basic Yellow 51(BY51), from aqueous solution by adsorption. Characterization of rice husk and burned rice husk was carried out with Scanning Electron Microscope and Fourier Transform Infrared Spectroscopy. The effects of operational parameters on the efficiency of dye removal including initial dye concentration, contact time, pH, and temperature were investigated. All series experiments were carried out in batch mode. Equilibrium data were analyzed using Langmuir and Freundlich isotherm models and monolayer adsorption capacity was calculated. Kinetic data were studied using pseudo first order and pseudo second order kinetic models and dye removal was found to follow the pseudo second order kinetic model closely. Thermodynamic parameters such as enthalpy change (H°), entropy change (S°) and free energy change (G°) were also investigated. Free energy change showed that adsorption of Basic Yellow 51 was spontaneous at all studied temperatures for rice husk and burned rice husk. It is proposed that rice husk and burned rice husk may be suitable as adsorbents for removal of cationic dyes from aqueous solution. [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]

3-Dimensional (3D) printable polymeric structures have lower mechanical properties than parts produced by existing conventional methods. It is still a challenge to obtain high elongation and more ductile on 3D polymeric structures even though photocurable resin cross linked with among polymer chains during UV-irridation and applied post-heat treatment steps. Filler materials as reinforcement agents such as silica, alumina, zirconia and multi-walled carbon nanotube, graphene, etc. were used to enhance its mechanical properties in the past decades. In this study, montmorillonite nanoclays including amine and silane functional group, which provides high dispersibility and homogeneity in photocurable resin, are added and mixed into acyrlate based photocurable resin with four different (pure, 0.25%, 0.5% and 1%) concentration. By using a 3D laser stereolithography printer, test samples are produced and characterized by tensile test, dynamic mechanical analyzer (DMA) and scanning electron microscope (SEM). As a result, it has been observed that by increasing the concentration of nanoclay, 3D polymeric structures gradually enhances its mechanical strength compared to pure polymer structures. Due to the agglomeration observed on %1 nanoclay concentration, their mechanical strength is lower than that of 0.5% nanoclay. Also, thermal stability gradually decreases with increasing nanoclay concentration due to its insulating properties. [ABSTRACT FROM AUTHOR]