Sun, Z. P.
Evis, Zafer
Pure and Mg(2+) & F(-) doped nano hydroxyapatites (HA) were synthesized by a precipitation method and sintered at 1100 degrees C to investigate their densification and structure. Different amounts of Mg(2+) and F ions were doped in to HAs. X-ray diffraction was used to identify the presence of phases And lattice parameters of HA and tri-calcium phosphates (TCP) present in the samples. Densification of HA was improved by the addition of these ions. In most of the doped samples, beta-tri-calcium phosphate (TCP) formation was observed as a second phase with the addition of Mg. Structure of the pure and doped samples were hexagonal and rhombohedral for HA and TCP, respectively.
33rd International Conference on Advanced Ceramics and Composites


Motameni, Ali; Evis, Zafer; -, -; Department of Engineering Sciences (2021-9-06)
In this thesis, mesoporous particles of β-tricalcium phosphate (βTCP, βCa3(PO4)2) and lanthanum (La) doped βTCP were synthesized by wet precipitation method attached with a microwave refluxing system. Pure dicalcium phosphate (DCP) and La modified dicalcium phosphate (La-DCP) bone cements were prepared based on acid/base reaction between βTCP (or La- βTCP) and monocalcium phosphate monohydrate (MCPM) in the presence of water. DCP bone cements were also mixed with 1.5-3.5wt.% of graphene oxide (GO). The obta...
Kinetic analyses of the effects of temperature and light intensity on growth, hydrogenm production and organic acid utilization by rhodobacter capsulatus
Sevinç, Pelin; Gündüz, Ufuk; Department of Biotechnology (2010)
Effects of temperature and light intensity on photofermentative hydrogen production by Rhodobacter capsulatus DSM1710 by use of acetic and lactic acids as substrates were studied. Experiments were conducted at 20, 30 and 38oC incubator temperatures under light intensities in the 1500 – 7000 lux range. pH of the medium and quantity of hydrogen forming together with quantity of biomass, and concentrations of acetic, lactic, formic, butyric and propionic acids in the medium were determined periodically. Growth...
Polybenzimidazole based nanocomposite membranes with enhanced proton conductivity for high temperature PEM fuel cells
Ozdemir, Yagmur; Uregen, Nurhan; DEVRİM, YILSER (2017-01-26)
In this study, phosphoric acid doped PBI nanocomposite membranes were prepared by dispersion of various amounts of inorganic nanoparticles in PBI polymer followed by phosphoric acid (H3PO4) doping for high temperature proton exchange membrane fuel cells (HT-PEMFC). All of the PBI composite membranes were cast from the same FBI polymer with the same molecular weight. Titanium dioxide (TiO2), silicon dioxide (SiO2) and inorganic proton conductor zirconium phosphate (ZrP) were used as inorganic fillers. The PB...
Raman Spectroscopy Investigation of Nano Hydroxyapatite Doped with Yttrium and Fluoride Ions
Yilmaz, Bengi; Evis, Zafer (Informa UK Limited, 2014-01-02)
In this study, nano hydroxyapatite doped with yttrium (2.5, 5, and 7.5mol%) and fluoride (2.5mol%) ions were synthesized by precipitation method and sintered at 900 degrees C, 1100 degrees C, and 1300 degrees C. Raman spectroscopy was applied to track the structural modifications in pure and doped hydroxyapatites. The results showed that the main characteristic band of pure hydroxyapatite at 963cm(-1) was not affected significantly by ion doping but exhibited higher intensity with increasing sintering tempe...
Synthesis and characterization of rare earth borophosphates
Özdil, Yasemin; Kızılyallı, Meral; Department of Chemistry (2004)
In this thesis, solid state reactions of Ln2O3, Y2O3, B2O3 and (NH4)2HPO4 were investigated to synthesize LnBP2O8 (Ln= Dy, Ho, Er) and YBP2O8 type of borophosphates which were not reported before. The products were analyzed by XRD, IR, DTA, SEM and EDX methods. In the first part of this thesis, synthesis of YBP2O8 through the solid state reaction of Y2O3 + 4(NH4)2HPO4 + B2O3 have been studied in the range 800-1140 °C. Orthophosphates of Dysprosium, Holmium, Erbium and Yttrium have tetragonal xenotime (YPO4)...
Citation Formats
Z. P. Sun and Z. Evis, “STRUCTURAL INVESTIGATION OF NANO HYDROXYAPATITES DOPED WITH Mg(2+) AND F(-) IONS,” Daytona Beach, FL, 2009, vol. 30, Accessed: 00, 2020. [Online]. Available: