Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395
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Article Citation - WoS: 23Citation - Scopus: 21The Measurements of Electrical and Thermal Conductivity Variations With Temperature and Phonon Component of the Thermal Conductivity in Sn-Cd Sn-In Sn-Ag and Sn-Bi Alloys(Elsevier France-editions Scientifiques Medicales Elsevier, 2016-02) Altintas, Yemliha; Kaygisiz, Yusuf; Ozturk, Esra; Aksoz, Sezen; Keslioglu, Kazim; Marasli, Necmettin; Kayglslz, Yusuf; Altlntas, YemlihaThe electrical and thermal conductivity variations with temperature for lead-free ternary solders, namely Sn-41.39 at.% Cd-6.69 at.% Sb, Sn-49 at.% In-1 at.% Cu, Sn-50 at.% Ag-10 at.% Bi and Sn-32 at.% Bi-3 at.% Zn alloys, were measured by the d.c. four-point probe method and radial heat flow apparatus, respectively. The contributions of electrons and phonons to the thermal conductivity were separately determined by using the measured values of the thermal and electrical conductivities obtained by the Wiedemann-Franz law in the lead-free ternary solders. The percentages of the phonon component of thermal conductivity were found to be in the range of 46-55%, 46-50%, 38-47% and 69-73% for Sn-41.39 at.% Cd-6.69 at.% SU, Sn-49 at.% In-1 at.% Cu, Sn-50 at.% Ag-10 at.% Bi and Sn-32 at.% Bi-3 at.% Zn alloys at the ranges of 318-443 K temperature, respectively. The temperature coefficients (alpha) of electrical conductivity for the lead-free ternary solders were found to be 2.47 x 10(-3), 4.97 x 10(-3), 1.14 x 10(-3) and 1.00 x 10(-3) K-1, respectively. The thermal conductivities of the solid phases at their melting temperature and the thermal temperature coefficients for the lead-free ternary solders were also found to be 47.72 +/- 2.38, 68.57 +/- 3.42, 73.52 +/- 3.67, 37.53 +/- 1.87 W/Km and 1.47 x 10(-3), 1.48 x 10(-3), 1.85 x 10(-3) and 2.21 x 10(-3) K-1, respectively. (C) 2015 Elsevier Masson SAS. All rights reserved.Article Citation - WoS: 6Citation - Scopus: 6Plasmon Enhanced Emission of Perovskite Quantum Dot Films(Cambridge Univ Press, 2018-01-09) Dadi, Seyma; Altintas, Yemliha; Beskazak, Emre; Mutlugun, Evren; Dadl, Seyma; Altlntas, YemlihaWe propose and demonstrate the photoluminescence enhancement of CsPbBr3 perovskite quantum dot films in the presence of Au nanoparticles. Embedded into a polymer matrix, Au nanoparticle-quantum dot film assemble prepared by an easy spin coating method enabled the photoluminescence enhancement of perovskite quantum dot films up to 78%. The properties of the synthesized perovskite QDs and gold nanoparticles have been analysed using high resolution transmission electron microscopy, X-ray diffraction, energy dispersive X-ray spectroscopy, UV-Vis absorption spectrophotometer, steady state and time-resolved photoluminescence spectrometer.Article Citation - WoS: 21Citation - Scopus: 21Efficient Forster Resonance Energy Transfer Donors of In(Zn)P/ZnS Quantum Dots(Amer Chemical Soc, 2017-01-26) Altintas, Yemliha; Talpur, Mohammad Younis; Mutlugun, Evren; Altlntas, YemlihaWe demonstrate a detailed investigation of the effect of the type and concentration of zinc precursor on the optical properties of In(Zn)P/ZnS quantum dots. We achieved up to 87% quantum yield along with 54 nm emission bandwidth for the green emitters with changing the concentration of the Zn precursors. Employing efficient green emitters as the donor species, we demonstrated an efficient Forster resonance energy transfer (FRET) couple of green and red emitting InP-based quantum dots. With a FRET efficiency level of 70.3% achieved (analyzed from the donor lifetime with and without an acceptor), we further demonstrated the enhancement of the acceptor emission nearly twofold due to the energy transfer. Our results provide new insights toward the understanding of the excitonic interactions among donor and acceptor quantum dots of the III-V family for light harvesting applications.