WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7150
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Article Citation - WoS: 10Citation - Scopus: 10The Role of Effective Catalysts for Hydrogen Production: a Performance Evaluation(Pergamon-elsevier Science Ltd, 2025) Goren, A. Yagmur; Temiz, Mert; Erdemir, Dogan; Dincer, IbrahimIn recent years, research on hydrogen (H2) production for alternative and environmentally-benign energy solution as fuel, storage medium and feedstock has been one of the most highly demanded subjects. It aims to reduce the pressures set by carbon dioxide emissions and the depletion of fossil fuel supplies. Nevertheless, largescale H2 production is limited by its high cost and low yield. The distinct photo-electrochemical characteristics of catalysts have shown them to have great promise for enhancing the production of H2. This article presents an updated and comprehensive review of enhanced H2 production using various catalysts in biological, thermochemical, and water-based processes. Various operational parameters (reactor configuration, catalyst dosage, catalyst type, catalyst modification methods, temperature, pH, and inoculum type) are summarized to improve the H2 production performance and reduce the environmental impacts and costs of these processes. For instance, in dark fermentation, biological H2 production is enhanced by 3.2-38 % with certain metal catalysts. Overall, results revealed that catalysts, specifically inorganic catalysts such as iron, nickel, titanium oxide, and silver, have improved the production rate of H2. This review has provided the application fields and working principles of catalysts in different H2 production processes. Finally, we suggested the main concerns that need to be prioritized in the long-term advancement of H2 production using catalysts.Article Proliferative Effects and Cellular Uptake of Ceramic Nanoparticles in Cancer and Normal Cells(Univ Chemistry & Technology, Prague, 2024) Cesmeli, Selin; Tomak, Aysel; Winkler, David A.; Karakus, Ceyda OkselThe high biocompatibility, wear resistance, and high surface area-to-volume ratios of calcium phosphate (CaP) nanoparticles make them materials of great interest for a very broad range of medical applications, such as dentistry, drug delivery, biomedical imaging, gene transfection and silencing, biomedical imaging, immunisation, and bone substitution. While their use as an enamel remineralisation agent, a bone substitution material, an implant coating, and drug/gene delivery agents is widely approved by the regulating bodies, insufficient attention has been paid to the interactions of CaP-based nanoparticles with cells and organs once in the bloodstream and distributed through the body. Here, three different CaP-based nanoparticles (CP: calcium phosphate, TCP: tricalcium phosphate, and HAp: hydroxyapatite) were examined for the proliferative effects, oxidative damage potential, and cellular uptake in the human embryonic kidney (HEK293) and pancreatic cancer (Panc-1) cell lines. The physicochemical properties of the nanoparticles were characterised by Teller analysis, and X-ray diffraction spectroscopy. Maximum proliferative effects were generated by 400 mu g center dot ml-1 TCP (220 %) in HEK293 cells. Interestingly, although CP nanoparticles had the highest reactive oxygen species formation capacity in the HEK293 cells, they exhibited the lowest proliferative effects and a relatively low internalisation rate, suggesting a minimal correlation between the cellular uptake level and oxidative potential.Article Citation - WoS: 3Citation - Scopus: 3Roadmap on Multifunctional Materials for Drug Delivery(IOP Publishing, 2024) Nottelet, Benjamin; Buwalda, Sytze; van Nostrum, Cornelus F.; Zhao, Xiaofei; Deng, Chao; Zhong, Zhiyuan; Cheah, Ernest; Kehr, Nermin SedaThis Roadmap on drug delivery aims to cover some of the most recent advances in the field of materials for drug delivery systems (DDSs) and emphasizes the role that multifunctional materials play in advancing the performance of modern DDSs in the context of the most current challenges presented. The Roadmap is comprised of multiple sections, each of which introduces the status of the field, the current and future challenges faced, and a perspective of the required advances necessary for biomaterial science to tackle these challenges. It is our hope that this collective vision will contribute to the initiation of conversation and collaboration across all areas of multifunctional materials for DDSs. We stress that this article is not meant to be a fully comprehensive review but rather an up-to-date snapshot of different areas of research, with a minimal number of references that focus upon the very latest research developments.Article Citation - WoS: 17Citation - Scopus: 19Development of Ca(oh)2-Based Geopolymer for Additive Manufacturing Using Construction Wastes and Nanomaterials(Elsevier, 2023) Mortada, Youssef; Masad, Eyad; Kogbara, Reginald B.; Mansoor, Bilal; Seers, Thomas; Hammoud, Ahmad; Karaki, AymanRecent growth in additive manufacturing (AM) or 3D printing in the construction field has motivated the development of various materials that vary in its composition and properties. This paper introduces, characterizes, and evaluates the performance of a sustainable and environmentally friendly geopolymer mixture composed of construction wastes. The geopolymer mixture has calcium hydroxide (Ca(OH)2) as the main alkaline activator and incorporates nanomaterials such as nano-silica and nano-clay to enhance its suitability for AM. The combined use of Ca(OH)2 for alkali activation, and nanomaterials for tailoring the behavior of construction wastes for 3D printing, is novel and addresses the shortcomings of conventional alkaline activators. The paper includes the outcomes of the analysis of the mechanical properties, printability, and microstructure of the geopolymer mixture. The 28-day compressive strength of the mixture reached 42 MPa with ambient temperature curing, which is comparable to traditional geopolymers. The inclusion of 1 wt % of nano-silica accelerated the geopolymerization process and led to the largest (35 %) reduction in the setting time. Similarly, incorporating 1 wt % of nano-clay led to reduction of the thermal conductivity from 0.709 W/mK to 0.505 W/mK, due to the introduction of thermal barriers. The printability of the studied waste-based geopolymer mixture was validated through the successful fabrication of a 3D-printed model. © 2023 The AuthorsConference Object Computational Nanotoxicology: a Case Study With Silver and Zinc Nanomaterials(Elsevier, 2022) Bilgi, Eyüp; Öksel Karakuş, CeydaNanomaterials (NMs) have been the focus of basic and applied research for more than two decades. According to the updated consumer materials inventory, over 1800 commercial NMs have taken their place in the market, 42% of which are in health and wellness category1. The widespread use of NMs in health-related products made not only the human exposure to the (residues of) NMs inevitable but also the long-recognized concerns over their safety a priority. Despite this pressing need, more than 70% of commercially available nano-containing products do not include sufficient information about their physicochemical and/or toxicological characteristics.Conference Object Development of Novel Nanotoxicity Assessment Method Utilizing 3d Printing System(Elsevier, 2022) Başlar, Muhammet Semih; Öksel Karakuş, Ceyda; Aldemir Dikici, BetülUnique physicochemical properties of nanomaterials (NMs) make them a material of choice in various applications but also raise concerns about their potential toxicity. While the commercial use of nano-enabled materials is growing rapidly, their interaction with biological systems and environment are not yet fully understood [1, 2]. Traditionally, toxicity of nano-sized materials are assessed by 2D cell culture models due to their time and cost-related advantages but their simplicity often comes at the cost of accuracy. While these methods are considered as the first step in toxicological assessment of both nanosized and bulk-form materials, they fall short in mimicking the complexity of in vivo physiological environments.Article Citation - WoS: 36Citation - Scopus: 38Investigation on Glassy Skin Formation of Porous Polystyrene Fibers Electrospun From Dmf(BME-PT, 2010) Demir, Mustafa MuammerMicrometer and submicrometer diameter of polystyrene (PS) fibers were electrospun from various dimethyl formamide (DMF) solutions at different weight fractions under 35% relative humidity. Increasing polymer fraction in the solution results in a gradual morphological transition from beads-with-incipient to bead-free fibers and also increases the diameter. The formation of uniform glassy skin presumably due to radial capillary flow within the liquid jet was confirmed by scanning electron microscope. The thickness of the skin varies with the weight fraction of PS; therefore, it was normalized with respect to average fiber diameter (AFD). The skin gets thinner as the weight fraction of PS increases. In addition, the fibers exhibit highly porous internal structure and smooth surface along with slight porosity. The development of porosity is attributed to liquid-liquid phase separation of water molecules in atmospheric moisture and DMF.