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Öğe Effect of coumarin concentration on the physical properties of CdO nanostructures(Elsevier Sci Ltd, 2014) Sahin, B.; Bayansal, F.; Yuksel, M.; Biyikli, N.; Cetinkara, H. A.In this work, nanostructured CdO films with different coumarin contents in the growth solution were fabricated on glass substrates by the HEAR method. The effects of coumarin content in the bath on optical, structural and morphological properties were studied by means of (UV-vis) spectrophotometer, SEM and XRD analysis. The analysis showed that the band gaps, surface morphologies and XRD peak intensities of the CdO films were found to change with coumarin content. A change in the band gap energy can be attributed to the improvement in crystallinity of the samples. XRD analysis showed that, the films have poly-crystalline structures with decent crystallinity levels. (C) 2013 Elsevier Ltd and Techna Group S.r.l. All rights reserved.Öğe Facile fabrication and characterization of SnxCu(1-x)O composite films by the SILAR method on glass substrates(Elsevier Science Sa, 2016) Bayansal, F.; Yuksel, M.; Sahin, B.CuO composite thin films with Sn-doping are deposited on glass substrates by the SILAR method. All the films are characterized by metallurgical microscopy, scanning electron microscopy, energy dispersive Xray spectroscopy, X-ray diffraction, UV-Vis. spectroscopy and Raman spectroscopy. Metallurgical microscopy and scanning electron microscopy results revealed that homogeneity of the film surface distorts and particle size decreases from 110 to 43 nm with increasing Sn-doping. Energy dispersive X-ray spectroscopy evidences the amount of Sn in CuO films, which increases with increasing Sn concentration in the growth solutions. X-ray diffraction patterns showed that the mean crystallite size of the films is decreasing from similar to 14 to similar to 9 nm with increasing Sn-doping. Moreover, increase in Sn concentration results new peaks belong to SnO2 phases. UV-Vis. analysis showed that the transmittance and optical band-gap energy values of the films are increasing with increasing Sn-doping. Raman spectrum was also confirmed the phase formation of CuO nanostructures and it was seen that the Sn-doping caused shifts in Raman active modes. (c) 2015 Elsevier B.V. All rights reserved.Öğe Influence of annealing to the properties of un-doped and Co-doped CdO films(Elsevier Sci Ltd, 2014) Sahin, B.; Bayansal, F.; Yuksel, M.; Cetinkara, H. A.Un-doped and Co-doped CdO nanostructures were deposited on glass substrates by successive ionic layer adsorption and reaction (SILAR) method and annealed at 300 and 400 C. Morphological, structural and optical properties of the films were investigated by scanning electron microscope (SEM), X-ray diffractometer (XRD) and ultra violet-vis (UV-vis) spectrophotometry. The analyzed results indicate that Co-doping concentration and annealing temperature affect the properties of nanostructure cadmium oxide (CdO) films. XRD results showed that all of the films are polycrystalline cubic CdO with good crystallinity levels. With UV-vis. analysis at the room temperature it was found that the doping and annealing temperature changed optical properties of CdO films. (C) 2013 Elsevier Ltd. All rights reserved.Öğe Influence of coumarin as an additive on CuO nanostructures prepared by successive ionic layer adsorption and reaction (SILAR) method(Elsevier Science Sa, 2013) Bayansal, F.; Sahin, B.; Yuksel, M.; Biyikli, N.; Cetinkara, H. A.; Guder, H. S.The effect of coumarin doping during the growth of CuO nanostructures by SILAR method has been studied. It was found that coumarin consider ably influences the growth process, manipulates the band-gap and modifies the crystallite size of the films. XRD experiments evidenced that with higher coumarin concentrations in the growth solution, the microstrain and dislocation density increased, while the crystallite size of the films decreased. SEM images revealed that the thicknesses of the plate-like nanostructures decreased with increasing coumarin concentration. By UV/vis spectrophotometer analysis it is found that the coumarin concentration affects both the optical band gap and the transmission rate: both the band gap and spectral transmittance values of the films decreased for higher coumarin content. (C) 2013 Elsevier B. V. All rights reserved.Öğe Influence of manganese concentration and annealing temperatures on the physical properties of CdO films grown by the SILAR method(Taylor & Francis Ltd, 2014) Sahin, B.; Bayansal, F.; Yuksel, M.Undoped and doped Cadmium oxide (CdO) films with different Mn concentrations were prepared on glass substrates by the successive ionic layer adsorption and reaction method and annealed at two different temperatures. Structural, morphological and optical conditions were performed by XRD, scanning electron microscope (SEM) and UV-vis spectrum measurements. The deposited films were dense and they adhere well to the glass substrates. From the SEM photographs, it was seen that Mn doping concentration and annealing process affect the morphologies of the nanostructures. It was found that the growth process modifies the microstructures of the CdO films. XRD results and UV-vis analysis reveal that the crystal structure and optical band gap of the films could be adjusted by varying the Mn concentration and annealing temperature. The results also indicate that there is a direct dependence of the physical and optical properties of the metal oxide films on doping concentration and annealing process.Öğe Modification of morphological, structural and optical properties of SILAR-based growth of CuO films on glass-slides by addition of dextrin(Elsevier Science Sa, 2014) Bayansal, F.; Sahin, B.; Yuksel, M.; Cetinkara, H. A.This paper presents the effect of dextrin addition to the growth solution to prepare CuO nanostructures by SILAR method. Structural, morphological and optical properties of the films were investigated by means of XRD, SEM and UV/Vis. analysis. From the XRD data it is found that with increasing dextrin concentrations in the growth solution the crystallite size of the films decreased. SEM images showed that dextrin addition has a decreasing effect on grain size and changes the morphology drastically. By UV/Vis spectrophotometer analysis it is found that the dextrin concentration increases both the optical band gap value and the transmission rate. (C) 2014 Elsevier B.V. All rights reserved.Öğe Nano structured CdO films grown by the SILAR method: Influence of silver-doping on the morphological, structural and optical properties(Elsevier Sci Ltd, 2016) Yuksel, M.; Sahin, B.; Bayansal, F.Cadmium oxide films with and without silver-doping have been prepared by the SILAR method onto soda-lime-silica glass slides and characterized by scanning electron microscopy, UV-Visible spectroscopy and X-ray diffraction measurements. Scanning electron microscopy images show that increasing silver concentration contributed to adjust surface properties and led to a decrease in particle size from the UV-Visible spectroscopy analysis it was found that the optical band gap value of the films is increased with silver doping. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved.Öğe NRF2 is a potential biomarker for the evaluation of weaning-related oxidative stress in goat kids(Hellenic Veterinary Medical Soc, 2022) Ozkan, H.; Kaya, U.; Karaaslan, I.; Dalkiran, S.; Camdeviren, B.; Yuksel, M.; Yakan, A.Weaning stress is crucial threatening factor in animal breeding. The aim of this study was to investigate the effects of weaning to oxidative stress and stress status of goat kids at the molecular levels. In the study, blood samples were collected at the weaning process (7 days before weaning- Pre-W, Day of weaning- Day-W and 7 days after weaning- Post-W)from 24 healthy Damascus goats. Cortisol, MDA (Malondialdehyde), COX-2 (Cyclooxygenase-2), and NRF2 (Nuclear factor erythroid 2-related factor 2) proteins levels were investigated in plasma, while COX-2 and NRF2 genes expression levels were determined from leukocytes. Compared to Pre-W, COX-2 gene was upregulated almost 2-fold in Day-W. On the other hand, NRF2 gene expression levels were tended to upregulation in Day-W, and it was upregulated approximately 2-fold in Post-W. While MDA levels were gradually increased in the weaning process, the levels of COX-2 and NRF2 proteins showed similar changes with gene expression trends. Positive correlations were also found between cortisol and COX-2 and NRF-2 protein levels in plasma. It was thought that significant outputs gained in terms of MDA levels in plasma of kids at the weaning process. For the first time, determination of COX2 and NRF2 levels both mRNA and protein levels in the weaning process of goat kids were satisfactorily evaluated in this study. Particularly, NRF2 was found to have the potential to be a fundamental biomarker to assess the oxidative status of weaning kids.Öğe SILAR-based growth of nanostructured CuO thin films from alkaline baths containing saccharin as additive(Elsevier, 2013) Bayansal, F.; Sahin, B.; Yuksel, M.; Cetinkara, H. A.Nanostructured CuO thin films were produced from alkaline baths containing saccharin as additive. X-ray diffraction analysis was used to determine the phase, crystallization and average crystallite size of the films. From the XRD analysis it was understood that the films have polycrystalline structure with monoclinic phases. The average crystallite size was also studied by the scanning electron microscopy. SEM images showed that the films were consisted of plate-like nanostructures with the thicknesses of similar to 25 nm. The effect of saccharin concentration on the transmission and optical band gap were also studied by UV-vis spectrophotometry. From the UV-vis spectra of the films it was seen that both the optical band gap and transmission properties of the films change with increasing saccharin concentration in the growth bath. (C) 2013 Elsevier B.V. All rights reserved.
