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    Activation energy for crystallisation of melt-quenched (Bi1.0Tl0.5Ga0.5) Sr2Ca2Cu3O10+y superconducting glass-ceramics
    (Academic Press Ltd, London, United Kingdom, 1997) Yakinci M.E.; Aksoy I.
    A glass of the BiSrCaCuO superconducting system with nominal (Bi1.0Tl0.5Ga0.5)Sr2Ca2Cu3O10+y composition has been prepared by the melt-quenched method. The crystallisation kinetics of the glass was investigated using non-isothermal analysis. The activation energy for crystallisation was found to be 420.6Kjmol-1. The superconducting transition and zero resistance temperatures were Tc = 118.8K and Tzero = 114.6K respectively. The calculated critical current density was Jc = 8.85 ×106 Acm-2 at 4.5K. In general, substitution of both Tl+3 and Ga+3 for Bi+3 increased the activation energy for crystallisation and enhanced the superconducting phase formation.
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    Crystallization Activation Energy and Hole Concentration Properties of the Bi2Sr2Ca1-xCdx, Cu2O8+y Glass-Ceramic Superconductor Rods
    (2002) Özhanh Z.; Yakinci M.E.; Balci Y.; Aksan M.A.
    The glass rods with the nominal compositions of Bi2Sr2Ca1-xCdxCu2 O8+y, where x = 0.0, 0.4, and 0.8, were prepared by melt-casting method. XRD studies exhibited that the Cd substitution caused a transition from Bi-2212 phase to Bi-2201 phase. The multiphase structure was obtained for higher Cd concentration cases. It was determined that the activation energy for crystallization was decreased with the increase of the Cd concentration. When the Cd concentration was increased in the system the superconducting properties decreased. The hole concentration, p, was calculated using the Presland's method. The increase in the Cd concentration increased the hole concentration and the results showed that the Cd-substituted samples were highly in the overdoped region. ©2002 Plenum Publishing Corporation.
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    Effects of SnO on growth and physical properties of BSCCO whiskers
    (2012) Altin S.; Aksan M.A.; Balci Y.; Yakinci M.E.
    Superconductor whiskers doped with SnO have been fabricated by annealing a melt quenched (Bi2Sn1)-223 precursor using suitable heat treatment cycles. Approximately 5 ?m thick, 90 ?m wide and 5 mm long whiskers were fabricated, and their physical, electrical and magnetic properties were investigated. Crystallisation activation energies of glass phase fabricated were calculated to be 390 kJ mol-1 using Kissinger method based on the differential thermal analysis data. The Tc value of the whiskers was found to be 94 K from M-T measurement. The magnetisation of whiskers before superconducting transition increased with decreasing temperature, and after superconducting transition, the magnetisation of whiskers decreased, from positive to negative, due to the diamagnetic nature of superconductivity. The change on magnetisation dependence of applied magnetic fields (M-H) showed that whiskers have paramagnetic-diamagnetic multiphase structure. © 2010 Institute of Materials, Minerals and Mining.
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    Interface structures and electrical properties of W/Si films grown by LPCVD
    (1996) Atici Y.; Yakinci M.E.; Ulu? B.; Aydo?du Y.
    Interface structures of W films on Si(100) substrates grown by LPCVD from a mixture of WF6, H2 and SiH4 (silane) gases at 280°C have been studied by transmission electron microscopy. Cross-sectional and plan-view samples were prepared to characterize the films. Consequently, according to the growth conditions, it has been observed that the W-Si interfaces are rough on a fine scale with some more extensive W protrusions in one of the samples which had an extended initial exposure to WF6. The W films have exhibited many randomly oriented grains ranging between 1000 and 4500 Å in size. Sheet resistance measurements have also been evaluated by means of four-point contact method at low temperatures (47-300 K) and it has been detected that the sheet resistance of a film decreases as the temperature decreases. © Tübi?tak.
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    Mapping of blood coagulation via image processing method
    (Institute of Electrical and Electronics Engineers Inc., 2016) Onar B.; Bayindir M.I.; Bilgili H.; Erkurt M.A.; Yakinci C.; Yakinci M.E.
    Biomedical applications based on image process algorithms are developed to aid doctors for diagnostic of some diseases. Several conventional tests are available about measuring blood coagulation such as PTZ, aPTZ, PTZ-INR. These tests are performed before every surgical operation even during some critical operations especially in cardiovascular and liver operations. Then, images are taken by a microscope connected to a computer in every 15 seconds, in such a way that 45 images are obtained till end of coagulation. These images are processed in an image processing algorithm in Matlab software. Hence, a graphical representation is produced for every subject. Results obtained from the proposed method prove that it can be a useful alternative to conventional methods. © 2015 IEEE.