https://hdl.handle.net/20.500.12960/14 2026-05-24T23:44:55Z 2026-05-24T23:44:55Z Gunduz Akdogan, Nilay Kalkavan, Duru Ghorbanighoshchi, Shabnam Akdogan, Ozan https://hdl.handle.net/20.500.12960/1825 2026-04-27T13:47:31Z 2026-01-01T00:00:00Z

From mill scale to Sr-ferrite permanent magnets; upcycling by additives Gunduz Akdogan, Nilay; Kalkavan, Duru; Ghorbanighoshchi, Shabnam; Akdogan, Ozan This study examines the sustainable production of strontium hexaferrite by recycling mill scale, a by-product of steel manufacturing, as a source of iron. Strontium, designated as a critical raw material by the European Union, is essential for high-demand magnetic applications. In this study, various additives, including Al2O3, Cr2O3, Co3O4, and La2O3, were incorporated during the synthesis process to enhance the magnetic properties of the resulting strontium hexaferrite. Additives were included in the structure using the mechanochemical method. The results show that the incorporation of these additives has a significant influence on the coercivity, remanence, and overall magnetic anisotropy of SrFe12O19.

2026-01-01T00:00:00Z Yin, Ran Zhang, Shunxin Jasim, Dheyaa J. Salahshour, Soheil Eftekharmanesh, Shabnam https://hdl.handle.net/20.500.12960/1802 2025-11-21T06:12:17Z

Fabrication and numerical analysis of non-metallic orthopedic prostheses using ultrasound techniques for reducing infection in sports-related injuries Yin, Ran; Zhang, Shunxin; Jasim, Dheyaa J.; Salahshour, Soheil; Eftekharmanesh, Shabnam Joint replacement has garnered considerable attention as a medical intervention for addressing sports-related joint injuries, offering the potential to restore sports activities and enhance quality of life. However, prioritizing safety measures and injury prevention during exercise is crucial. The increasing prevalence of infections in knee arthroplasty surgeries is a significant concern for both patients and surgeons, emphasizing the necessity for implants with proven efficacy against periprosthetic joint infections (PJI). In this study, two samples were prepared: sample 1 comprised pure copper nanoparticles, while sample 2 consisted of copper nanoparticles supplemented with titanium nanoparticles (TiNP) using the powder metallurgy (PM) technique. The copper prosthesis was characterized using X-ray diffraction (XRD), scanning electron microscope (SEM), and compressive strength tests. The biological behavior of the samples was evaluated in simulated body fluid (SBF) and phosphate buffer saline (PBS) over 3 months. The results demonstrated that the fabricated copper prosthesis exhibited a mesoporous microstructure, with a specific surface area ranging from 150 to 200 (cm2/g). The samples displayed porosity levels of 25 % to 32 %, with pore volumes ranging from 50 to 100 nm. The addition of TiNP to the copper nanoparticles reduced the specific surface area and pore volume of the prosthesis. Cell viability and electrical conductivity assessments revealed the formation of a thin apatite layer on the surface of the copper sample with added titanium nanoparticles. This study leverages the unique capabilities of ultrasound technology to fabricate and evaluate the performance of these novel prosthetic components. The inclusion of TiNP decreased the dissolution rate and increased apatite formation. Moreover, the mechanical properties of the prosthesis improved, and its biological behavior was enhanced, resulting in the development of a beam-shaped biological implant that was analytically analyzed. The addition of approximately 10 wt% TiNP was found to be effective in improving the mechanical and biological properties of the copper-titanium implant.

Erol, Erdeniz Cansoy, C. Elif Aybar, Orhan Özgür Beşikçi, Elif Bal https://hdl.handle.net/20.500.12960/1798 2025-11-21T05:50:19Z 2025-01-01T00:00:00Z

The Impact of Fouling on Ship Energy Efficiency in Dual-Fuel Engine and Battery Hybrid Electric Ferry Operation Erol, Erdeniz; Cansoy, C. Elif; Aybar, Orhan Özgür; Beşikçi, Elif Bal This chapter presents a comprehensive analysis of fouling impact on operational ship energy efficiency in a dual-fuel engine and battery hybrid electric vessel. Utilizing raw data obtained from the vessel data sources coupled with physical parameters, the study employs a data-driven approach to detect anomalies and assess the impact of fouling on the operational energy efficiency of ships. Through elaborate data-driven analysis and modeling techniques, the chapter also reviews the correlation between fouling accumulation and energy consumption patterns. The data-driven approach allows for the identification of specific operational parameters affected by fouling, such as propulsion efficiency and power consumption. Studies have shown that even a thin slime layer, measuring only 0.5 mm and covering up to half of the hull’s surface, can potentially lead to a 25–30% increase in greenhouse gas emissions, depending on the ship’s characteristics, operating speed, and environmental conditions. Investigation into the automated inspection and cleaning process reveals that a measured reduction in biofouling on ship hulls leads to an approximate 10% decrease in energy consumption. The findings contribute to a deeper understanding of the interplay between fouling, energy efficiency, and hybrid propulsion systems, providing valuable insights for optimizing vessel performance and informing proactive fouling management strategies. Ultimately, this research supports the transition towards sustainable maritime transportation practices through enhanced operational efficiency and reduced environmental impact.

2025-01-01T00:00:00Z Öz, Umut Can Küçüktürkmen, Berrin Gómez, I. Jénnifer Elsherbeny, Amr İpek Tekneci, Seda Eşim, Özgür Göksever, Selin Özköse, Umut Uğur Gülyüz, Sevgi Bazán-Cobelo, Claudia https://hdl.handle.net/20.500.12960/1792 2025-11-19T10:34:48Z

Engineering Two-in-One Nanoparticles for Simultaneous Delivery of Graphene Quantum Dot and Pemetrexed Öz, Umut Can; Küçüktürkmen, Berrin; Gómez, I. Jénnifer; Elsherbeny, Amr; İpek Tekneci, Seda; Eşim, Özgür; Göksever, Selin; Özköse, Umut Uğur; Gülyüz, Sevgi; Bazán-Cobelo, Claudia The simultaneous delivery of therapeutic agents and imaging probes using polymeric nanoparticles (NPs) has gained significant attention for cancer treatment. In this work, we developed a multifunctional nanocarrier system composed of an amphiphilic block copolymer, poly(2-ethyl-2-oxazoline)-b-poly(ε-caprolactone) (PEtOx-b-PCL), and dimethyldidodecylammonium bromide (DDAB), for the codelivery of the chemotherapeutic drug pemetrexed (PMT) and nitrogen- or sulfur-doped graphene quantum dots (N-GQDs or S-GQDs) as fluorescent probes. Critical formulation parameters were optimized using a central composite design (CCD). The optimized NPs exhibited favorable physicochemical properties, including positive surface charge (6–8 mV), hydrodynamic diameters of ∼140 nm, and high encapsulation efficiency for both PMT (46–56%) and GQDs (>98%). In vitro assays revealed that PMT-loaded nanoparticles (NPs) significantly enhanced cytotoxicity against MCF-7 cells. At a concentration of 2 ppm after 72 h, N-PMT NPs and S-PMT NPs inhibited cell proliferation by 50.7% and 53.8%, respectively, compared to 37.8% inhibition with free PMT at the same dose. Confocal microscopy confirmed efficient intracellular uptake and strong fluorescence signals, supporting their potential for bioimaging. Collectively, these results demonstrate that this two-in-one nanocarrier system significantly enhances chemotherapeutic efficacy while enabling real-time imaging, establishing a promising platform for drug delivery and noninvasive treatment monitoring in cancer nanomedicine.