Yazar "Yilmaz, O." seçeneğine göre listele
Listeleniyor 1 - 3 / 3
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Effect of molar concentration on the structural, linear and nonlinear optical properties of CuS (covellite) thin films(Pergamon-Elsevier Science Ltd, 2022) Habiboglu, C.; Erken, O.; Gunes, M.; Yilmaz, O.; Cevlik, H. C.; Ulutas, C.; Gumus, C.CuS thin films with various molar concentrations at 70 degrees C temperature were deposited by Chemical Bath Deposition. The effect of molar concentration on the structural, linear optic, nonlinear optic and morphological properties of CuS films were deeply investigated. X-ray diffraction (XRD) analysis exhibited that CuS films were formed in polycrystal structure and hexagonal phase. The fundamental optical parameters of films such as energy band gap, reflection and extinction coefficient were determined with the results of optical transmission and optical absorption by UV-vis spectrophotometer. The energy band gap values were reduced with increasing films thickness. Moreover, the dependence of the optical dielectric constants, loss tangent, optical conductivity, surface and volume energy loss function values on the molar concentrations were studied. Furthermore, the third order nonlinear optical susceptibility and nonlinear refractive index, which is considered to be the base of the first order optical susceptibility with nonlinear optical properties were discussed in detail.Öğe THE EFFECTS OF DARBEPOETIN ON PERITONEAL FIBROSIS INDUCED BY CHEMICAL PERITONITIS AND ON PERITONEAL TISSUE MMP-2 AND TIMP-2 LEVELS IN RATS(Sage Publications Inc, 2009) Borazan, A.; Camsari, T.; Cavdar, Z.; Sarioglu, S.; Yilmaz, O.; Oktay, G.; Sifil, A.The aim of this study is to assess the influence of darbepoetin on the development of peritoneal fibrosis in rats induced by chlorhexidine gluconate (0.1%) and ethanol (15%) and to determine the effect on peritoneal tissue levels of MMP-2 and TIMP-2, possible important factors in progression of peritoneal fibrosis. Twenty-four female Wistar albino rats were divided into three groups. The first group (CH group) received 3 ml/200g daily intraperitoneal injections of chlorhexidine gluconate (0.1%) and ethanol (15%) dissolved in saline to induce chemical peritonitis; group 2 (ESA group) received 3 ml/200g daily injections of chlorhexidine gluconate (0.1%) and ethanol (15%) dissolved in saline and also darbepoetin 12.5 microgr/per kilogram/day subcutaneously on the first and seventh days; group 3 (Control group) received intraperitoneal 0.9% saline (3 ml/200g/d) through the right lower quadrant by 21 gauge needle. The study duration was fourteen days. On the fifteenth day rats were sacrificed, parietal peritoneum samples were obtained from the left anterior abdominal wall. Pathological samples were examined using Hematoxyline & Eosin (HE) stains. The thickness, vasculpathy, and inflammation were determined by light microscopy. MMP-2 and TIMP-2 were studied immunohistochemically by monoclonal antibody staining. The activity of MMP-2 on peritoneal tissue was studied by gelatin zymography and TIMP-2 protein level was analysed by ELISA, biochemically. The decrease in thickness of parietal peritoneum in group ESA was statistically significant when compared to CH group (p<0.05). Inflammation scores, and vascularization score surfaces were not statistically different between these groups (p>0.05). Immunohistochemically, darbepoetin was shown to decrease MMP-2 expression on parietal peritoneum in CH group (p<0.05), but had no effect on TIMP-2 (p>0.05). Biochemically the ratio of active MMP-2 to proMMP-2 was more significantly increased in the ESA group than in the CH group (p<0.001), however, TIMP-2 levels in both groups were decreased compared to the control group (p<0.05). Darbepoetin histopathologically reduced peritoneal fibrosis induced by chlorhexidine gluconate. We can suggest that Darbepoetin does not cause peritoneal fibrosis and may prevent peritoneal fibrosis in rats possibly related to an effect on MMP-2 expression. Further research regarding the utility and dosage should be considered.Öğe The influence of trisodium citrate dihydrate complexing agent on the structural, electrical and optical properties of ?-MnS thin films(Springer, 2023) Budak, Z.; Ulutas, C.; Yilmaz, O.; Cevlik, H. C.; Gunes, M.; Gumus, C.gamma-MnS films were prepared using trisodium citrate (TSC) complexing agents at different molarity values (0.5, 1 and 1.5 M). Characterization techniques such as X-ray Diffraction (XRD), optical absorption spectra, Field Emission-Scanning Electron Microscope (FE-SEM), Energy Dispersive X-ray (EDX) and Hall Effect were used to determine the properties of the films. As a result of XRD analysis, it was observed that the films prepared with 0.5 M TSC were formed in amorphous structure, while the films prepared with 1 M and 1.5 M TSC were formed in polycrystalline structure and hexagonal phase. In addition, it was determined that the crystallization of the films increased with the increase in the molarity of TSC. The optical gaps of the films were determined as 3.77 eV, 3.44 eV and 3.40 eV, respectively, depending on the increase in molarity of TSC. The refractive index values of the MnS films in the visible region (400-700 nm) were calculated as 1.87, 2.02 and 2.10, respectively. Electrical resistivity and mobility values from Hall Effect measurements were measured as 1.01 x 10(6), 9.68 x 10(5), 4.10 x 10(5) ohm cm and 33.01, 36.93, 56.53 cm(2)/Vs, respectively, depending on the increase in TSC molarity value.
