Yazar "Tuncer, Y." seçeneğine göre listele

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    CATHODOLUMINESCENCE RESPONSE FROM RARE EARTH DOPED Bi4Ge3O12
    (ELSEVIER SCIENCE BV, 2009) Kibar, R.; Cetin, A.; Tuncer, Y.; Uysal, S.; Townsend, P. D.; Canimoglu, A.; Can, N.; Boulon, G; Dujardin, C; Jurdyc, AM
    Room and low temperature cathodoluminescence (CL) of rare earth doped Bi4Ge3O12 (BGO) has been recorded. Luminescence signals noted in the wavelength range (300 - 800 nm) include intrinsic broad emission bands and signals related to Eu3+, Nd3+, and Tm3+. CL measurements made on Bi4Ge3O12 (BGO) doped with rare earth ions are reported for the temperature range 40 to 300 K with different CL excitation modulation frequencies. Dopant levels used in the present study are 1.1, 0.4, and 0.3 wt% Nd, 0.4 wt% Tm and 3 ppm Eu. All dopant levels exhibited different CL spectra with evidence for lines due to the rare-earth dopants intra-4f transitions. The temperature dependence of the intensity of the emission band is discussed.
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    Luminescent, Structural, and Thermal Properties of the Unusual "Anatolian" Diaspore (Zultanite) from Turkey
    (TAYLOR & FRANCIS INC, 2014) Canimoglu, A.; Garcia-Guinea, J.; Correcher, V.; Karabulut, Y.; Tuncer, Y.; Can, N.
    Results are presented for the cathodoluminescence (CL) probe of an environmental scanning electron microscopy (ESEM) with an energy-dispersive spectrometry analyzer (EDS), thermoluminescence (TL), thermo X-ray diffraction in situ (TXRD), and simultaneous differential thermal analysis and thermogravimetric analysis (DTA/TGA) techniques of gem-quality zultanite samples collected from the Mugla region of southwest Turkey. Micro-Raman measurements were also performed on different zultanite orientations and preheated aliquots to study the spectral phase transition diaspore-corundum also detected by the other thermal techniques in the 450 degrees C-500 degrees C thermal range. The thermal phenomena of TL are synchronous with this dehydroxylation process, involving consecutive breaking-linking bonds of Al-O, Cr-O, Fe-O, Al-OH, Cr-OH, and Fe-OH, including the formation of hydrolyzed ions such , and and redox reactions. Assuming that zultanite oxygen atoms are distributed as a hexagonal close packed layer, the experimental spectrum CL of zultanite is characteristic of the E-2 ->(4)A(2) transitions of substitutional Cr3+ luminescent centers in positions of Al3+ in sixfold coordination.