Merkezler / Centers
https://hdl.handle.net/11352/71
2024-03-29T00:29:30ZDevelopment of an Alternative Heat Treatment to the Traditional T6 Heat Treatment of AlSi10Mg Alloy Produced by Additive Manufacturing
https://hdl.handle.net/11352/4880
Development of an Alternative Heat Treatment to the Traditional T6 Heat Treatment of AlSi10Mg Alloy Produced by Additive Manufacturing
Tütük, İbrahim; Ural, Mehmet Moğoltay; Yılmaz, Mustafa Safa; Özer, Gökhan
In this study, alternative solution heat treatments, applied at lower temperatures and shorter times, were
applied to AlSI10Mg samples produced with the powder bed laser fusion technique. Thermocalc software
was used to determine the temperatures of the NT6 solution heat treatment. The samples were analyzed by
optical microscope, scanning electron microscope, energy-dispersive x-ray analysis, x-ray diffractometer
and their mechanical behavior was examined. The results were compared with traditional T6 heat treatments
and it was determined that the samples showed better ductility after NT6 heat treatments while
maintaining the strength values in the traditional method.
2024-01-01T00:00:00Zİslam Öncesi ve Sonrası ile Ayasofya Camii Geometrik Desenlerinin Mukayeseli Analizi
https://hdl.handle.net/11352/4810
İslam Öncesi ve Sonrası ile Ayasofya Camii Geometrik Desenlerinin Mukayeseli Analizi
Sönmez, Serap Ekizler
Bu çalışmada Ayasofya Camii’nde yer alan geometrik desenlerin pergel-cetvel (çizgilik) konstrüksiyonu ile çizimine ve
arkalarında yatan geometrik sistemlere odaklanılmıştır. Neredeyse tüm İslam coğrafyasında sayısız örnekle ve özellikle 9.
yüzyıldan sonra daha ileri pergel-cetvel konstrüksiyon bilgisi gerektiren tasarımlarla karşımıza çıkan geometrik desenleri
İslam Dönemi’nin âdeta bir kimliği hâline getiren özellikler vardır. Bilim ve sanatın kesişim kümesinde olan geometrik
desenler, genellikle yapısındaki geometri göz ardı edilerek sadece tespitler üzerinden bilimsel çalışmalara yansımaktadır.
Pergel-cetvel konstrüksiyonu ile bir desenin inşası kaynağını Öklid (MÖ 3. yüzyıl) geometrisinden almaktadır.
Bu çalışmada, geleneğe ait olan bu inşa metodu kullanılarak Ayasofya Camii’nde yer alan desenlerin analizleri yapılmış ve
İslam Öncesi Dönem uygulamaları ile sonrasında ortaya konulan desenler mukayese edilmiştir. Ayasofya özelinde yapılan
bu mukayese ile birlikte genel bir İslam öncesi ve sonrası sürecine dair değerlendirmede bulunulmuştur. Desenlerin
analizinde ilk kez bu makale ile literatüre kazandırılan “nizamî” kelimesine açıklık getirilerek doğru bir konstrüksiyon
için önemine değinilmiştir. Bunların neticesinde genel olarak geometrik desenleri tanımlarken kullanılan başlıklarda
“İslam” kelimesinin yer almasının sebepleri masaya yatırılmıştır. İlave olarak cami minberinde yer alan desenlerin yapısı
üzerinden Ayasofya Camii minberinin tarihlendirilmesine dair bir öneride bulunulmuştur. Bu çalışma ile birlikte sanat
tarihi bağlamında ele alınan geometrik desenlerin analiz boyutu ile bilim tarihi, hatta kültür tarihi yazımı için de bir
vesika değeri taşıyıp taşımadığı sorgulanmıştır.
2024-01-01T00:00:00ZEnhancement of Cytotoxic and Apoptotic Activity Through Oolong Tea Extract-mediated CuO/Cu2O Nanoparticles
https://hdl.handle.net/11352/4809
Enhancement of Cytotoxic and Apoptotic Activity Through Oolong Tea Extract-mediated CuO/Cu2O Nanoparticles
Karakuş, Emir Ersel; Sert, Esra; Erol, Ayşe; Kalındemirtaş, Ferdane Danışman; Özbaş, Fatih; Karakuş, Selcan
The development of multifunctional nanoformulations with enhanced anticancer activity and drug delivery potential is of increasing scientific importance. In this study, we synthesized and characterized copper oxide nanoparticles mediated by oolong tea extract (OE-CuO/Cu2O NPs) using a variety of techniques, including TEM, XRD, FTIR, and UV–Vis spectroscopy, to assess their physical and chemical properties. Remarkably, the results revealed that OE/CuO NPs exhibited significantly enhanced anticancer activity compared to OE alone. The effects of OE and OE-CuO/Cu2O NPs were on cytotoxicity, apoptosis, and cell cycle progression. Furthermore, we assessed the impact of these nanostructures on CD44/24 antibodies, known as aggressive cell markers, following treatment. The green OE-CuO/Cu2O NPs displayed remarkable inhibitory effects on colon cancer HCT116 and breast cancer cells MCF-7 cells. It was shown that OE-CuO/Cu2O NPs reduced the production of the CD44 antibody, provided cell cycle arrest, and encouraged apoptosis. More specifically, it was discovered that these NPs caused MCF-7 cells to undergo apoptosis and G2/M phase cell cycle arrest. Additionally, drug delivery investigations were conducted to evaluate the potential of OE-CuO/Cu2O NPs as drug nanocarriers, further underscoring their promise in developing novel anticancer agents with significant cytotoxic, apoptotic, and drug delivery properties.
2024-01-01T00:00:00ZSustainable Synthesis of Green Cu2O Nanoparticles using Avocado Peel Extract as Biowaste Source
https://hdl.handle.net/11352/4713
Sustainable Synthesis of Green Cu2O Nanoparticles using Avocado Peel Extract as Biowaste Source
Özbaş, Fatih
In recent years, there has been a significant shift towards the production of advanced nanomaterials
using sustainable methods, reflecting a heightened focus on reducing environmental impact and optimizing
resource utilization. This growing interest stems from the necessity to address environmental concerns and
embrace eco-friendly practices in material synthesis. The primary objective of this study is to explore the ecofriendly synthesis of novel metal oxide nanoparticles (NPs) by utilizing bio-waste as a sustainable precursor. The
central theme revolves around employing ultrasound-assisted techniques for Cu2O NP synthesis, with a specific
emphasis on utilizing avocado peel waste as an effective phytochemical compound for capping. Through
systematic process optimization, we conducted a comprehensive assessment of the resulting NPs, delving into
their chemical, thermal, and surface properties. Advanced characterization techniques, including X-ray Diffraction
analysis (XRD), Transmission Electron Microscopy (TEM), Thermogravimetric Analysis (TGA), Differential Scanning
Calorimetry (DSC), and Fourier-transform Infrared Spectroscopy (FT-IR), were employed to gain profound insights
into the attributes of the synthesized NPs. Our experimental results conclusively demonstrate the successful
synthesis of spherical Cu2O NPs, each with a diameter of 25 ± 2 nm. This was achieved by utilizing avocado peel
waste (APW) and ultrasound-assisted cavitation at room temperature. The study significantly contributes to our
understanding of the potential applications of green synthesis methods, paving the way for environmentally
friendly and cost-effective Cu2O NPs.
2024-01-01T00:00:00Z