Yazar "Emek, Mehriban" seçeneğine göre listele
Listeleniyor 1 - 2 / 2
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Electromagnetic Shielding Performances of Colemanite PANI / SIO2 Composites in Radar and Wider Frequency Ranges(Beykent Üniversitesi, 2020) Şahin, Ethem İlhan; Emek, Mehriban; Ertuğ, Burcu; Kartal, MesutIn this study, colemanite-SiO2 were produced by using mixed oxide technique. The composition was formed with various proportions for the structural analysis. The results of the structural analysis indicated that second phase did not form in colemanite and SiO2. Addionality, the colemanite/ polyaniline/SiO2 composites were produced by hot pressing using the compositions of colemanite- SiO2 in different proportions and aniline. The weight ratios of colemanite-SiO2 and aniline were 1:1 respectively and epoxy resin was used to produce microwave shielding composites. The microwave shielding performances of colemanite/polyaniline/SiO2 composites were investigated by shielding effectiveness in 8 –18 GHz using two–port vector network analyzer. A minimum of – 41.1 dB shielding effectiveness performance was obtained in 16.09 GHz at the thickness of 1.5 mm. This shielding performance can be modulated simply by controlling the content of polyaniline and content of colemanite-SiO2 in the samples for the required frequency bands.Öğe Structural and dielectric performance of the Ba(Zn1/3Nb2/3-xSbx)O3 perovskite ceramics(Iop Publishing Ltd, 2019) Qasrawi, A. F.; Sahin, Ethem Ilhan; Emek, Mehriban; Kartal, Mesut; Kargin, SerdarIn this work, we have explored the antimony doping effects on the structural and dielectric properties of Ba(Zn1/3Nb2/3)O-3 ceramics (BZN). The ceramics displayed perovskite structures with a lattice constant that decreases with increasing Sb content. The antimony solubility limit of the BZN ceramics is x < 0.50. Belowthis limit and in the range of 0.30 <= x <= 0.40, the microstrain, the dislocation density and the stacking faults decreased and the crystallite size increases with increasing Sb content in the composition of BZN. When the limit is exceeded minor phases are predicted by software analysis and confirmed by the experimental techniques. The presence of these phases is also verified by the scanning electron microscopy and energy dispersive x-ray spectroscopy techniques. Increasing the Sb content is observed to decrease the value of the dielectric constant. The Sb doped BZN ceramics exhibits high dielectric quality factors that nominate it for applications in electronics as radio waves resonators.