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    An Unusual Cervical Mass in the Hyoid Bone: Intermediate-Grade Chondrosarcoma
    (Hindawi Ltd, 2019) Caglar, Ozge; Karatag, O.; Avci, A.; Derekoy, Sefa
    We describe a case of a 31-year-old woman with a chondrosarcoma of the hyoid bone. The patient presented with a mass in the left submandibular region. Fine-needle aspiration cytology suggested chondroma, but further imaging investigation with CT revealed an exophytic tumor originating from the body of the hyoid bone. Histopathology of the surgical specimen confirmed the diagnosis of a intermediate-grade chondrosarcoma. Chondrosarcomas account for 11% of all bone cancers. Primary sites of the head and the neck include the nasal cavity, the skull base, the maxilla, the mandible. Chondrosarcomas of the hyoid bone are very rare, with only 23 cases previously reported in the literature.
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    Fast production of ZnO nanorods by arc discharge in de-ionized water and applications in dye-sensitized solar cells
    (Elsevier Science Sa, 2014) Sonmezoglu, S.; Eskizeybek, V.; Toumiat, A.; Avci, A.
    Fast production of the ZnO nanorods by bottom up approach using arc discharge method in de-ionized water was carried out. Structural analysis showed that the obtained ZnO powder exhibits crystallize in the hexagonal wurtzite structure with (101) preferential orientation. Furthermore, transmission electron microscopy observations showed that rod-like structure is the abundant form with a bimodial grain size distribution around 10 and 30 nm. Optical characterization of the as-synthesized ZnO nanorods revealed the existence of the two absorption and photoluminescence (PL) bands both located at UV spectral region attributed to the two grain size distributions. In addition, the two additional visible bands PL spectrum located at 430 and 492 nm are attributed the interstitial zinc and oxygen vacancies; respectively. Dye sensitized solar cells (DSSCs) were successfully produced via different ruthenium based dyes and ferrocene liquid electrolyte by using of as synthesized ZnO nanorods modified photoanodes. It has been found that DSSCs made with N719 dye is the most efficient with photoconversion of approximately 7% compared to the other dyes. Such nanorod form of the ZnO nanostructures with ruthenium dyes resulted in significant improvements of the device performance in terms of electron transportation and UV light absorption. This work would explore feasible routes to synthesize efficient metal-oxide nanostructures for opto-electronic or other related applications. Published by Elsevier B. V.
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    Optical Constants of Thin Film Prepared by the Cd(OH)2 Nanowires Synthesized Using the Arc Discharge Method
    (Amer Scientific Publishers, 2014) Akin, U.; Safak, H.; Eskizeybek, V.; Avci, A.; Yuksel, O. F.
    The optical constants of thin film prepared by cadmium hydroxide nanoparticles spray coated on the glass substrate held about at 100 degrees C temperature have been investigated using the optical transmission and reflection spectra. The transmission spectrum exhibits that the film has a high transparency (similar to 80%) at the infrared region. From standard optical analysis, direct band gap energy of Cd(OH)(2) was found as 3.13 eV, and also, it was seen that the calculated refractive index varies between 1.65 and 2.15 throughout the spectral region considered. The dispersion parameters such as oscillator energy, dispersion energy, and static and high frequency refractive index were determined in regard to the Wemple DiDomenico single oscillator model. Finally, some dielectric parameters of material such as relaxation time, dissipation (loss) factor, volume and surface energy loss functions and optical conductivity were calculated.