Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Book Part A Study on Absorption and Reflection of Infrared Light by the Uncoated and Al Coated Surfaces of Polymer Films Techniques(Apple Academic Press, 2014) Arkış, Esen; Balköse, DevrimPolymer films coated with a thin layer of aluminum or aluminum oxide are extensively used in food packing as heat shields. The infrared rays were not transmitted through the films and were reflected protecting the contents from the harmful effects of infrared light. The quantitative measurement of the film thickness and infrared light reflection and absorption capacities of aluminum coated films used as packing materials were possible using infrared spectroscopy. © 2015 by Apple Academic Press, Inc.Book Part Advances in Nanocomposite Membranes for CO2 Removal(Elsevier, 2024) Marpani,F.; Othman,N.H.; Alias,N.H.; Mat Shayuti,M.S.; Alsoy Altınkaya, SacideNanocomposite membranes have emerged as a promising solution for efficient carbon dioxide (CO2) removal in gas separation processes. These membranes combine polymeric matrices with inorganic nanofillers to synergize the excellent separation performance of inorganic materials with the mechanical stability of polymers. The choice of nanofillers, such as porous and nonporous materials, significantly influences the gas permeability and selectivity of the resulting nanocomposite membranes. Porous fillers with interstitial channels and large surface areas are found to selectively adsorb CO2, enhancing membrane separation performance. On the other hand, nonporous fillers alter the polymer chain orientation, influencing gas separation differently. The 1D, 2D, and 3D morphologies of nanofillers offer unique properties in terms of surface-to-volume ratio, permeability, and selectivity. The fabrication of nanocomposite membranes also plays a crucial role, and advances in materials and manufacturing techniques have enabled the design of high-performing membranes. Asymmetric and symmetric configurations have been explored to optimize separation efficiency. Nevertheless, challenges such as aging, compaction, and swelling need to be addressed to ensure the long-term stability of nanocomposite membranes. Future research should focus on developing advanced theoretical models to better predict gas permeation behaviors in these membranes. Overall, nanocomposite membranes offer a promising avenue for efficient CO2 removal, contributing to sustainable environmental practices and energy production. © 2024 Elsevier Ltd. All rights reserved.Book Part Calcium Soap Lubricants(CRC Press, 2015) İzer, Alaz; Kahyaoğlu, Tuğçe Nefise; Balköse, DevrimThe reparation and characterization of calcium stearate (CaSt2) and a lubricant by using calcium stearate were aimed at in this study. Calcium stearate powder was prepared from sodium stearate and calcium chloride by precipitation from aqueous solutions. CaSt2 and the Light Neutral Base oil were mixed together to obtain lubricating oil. It was found that CaSt2 had a melting temperature of 142.8 °C and in base oil it had a lower melting point, above 128 °C. It was dispersed as lamellar micelles as the optical micrographs had shown. From rate of settling the size of dispersed particles were found to be 1.88 µm and 0.11 µm for lubricants having 1% and 2% CaSt2, respectively. The friction coefficient and wear scar diameter of base oil 0.099 and 1402 nm were reduced to 0.0730 and 627.61 nm respectively for the lubricant having 1% CaSt2. Lower wear scar diameter (540 nm) was obtained for lubricant with 2% CaSt2. CaSt2 improved the lubricating property of the base oil but did not improve its oxidative and thermal stability. © 2015 by Apple Academic Press, Inc.Book Part Citation - Scopus: 3Tissue Engineering Applications of Marine-Based Materials(Springer, 2022) Polat, Hürriyet; Zeybek, Nuket; Polat, MehmetTissue engineering is a promising approach in replacing or improving tissues lost or has become nonviable due to disease or trauma by the use of scaffold materials by combining engineering and biochemical/physicochemical methods. Its purpose is to create suitable matrices that support cell differentiation and proliferation toward the formation of new and functional tissue. Marine-based natural compounds are potential scaffold feedstock material in tissue engineering owing to their biocompatibility and biodegradability while providing excellent biochemical/physicochemical properties. Numerous application areas and various fabrication routes techniques described in the literature attest to the importance of these materials in tissue regeneration. This review has been carried to merge the information from a large number of studies on the marine-based scaffold materials in tissue engineering into a coherent summary. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2022.Conference Object Numerical Study on the Mixing Characteristics in the Argon Oxygen Decarburization Process(Association for Iron and Steel Technology, AISTECH, 2022) Cheng, Zhongfu; Wang, Yannan; Dutta, Abhishek; Blanpain, Bart; Guo, Muxing; Malfliet, AnneliesThe argon-oxygen decarburization (AOD) process is a crucial refining method in modern stainless steel production. It has been widely used to remove C in the past few decades [1, 2]. The AOD converter can provide excellent mixing conditions through turbulent stirring using submerged tuyeres. In the AOD process, the flow characteristics in the bath have a significant influence on the mass transport, momentum exchange and heat transfer, which are closely linked with the gas-metal reaction kinetics and the refining efficiency. A deep understanding of jet behavior, bubble flow characteristics and mixing efficiency facilitates further optimization of the decarburization and desulfurization operations. This will increase the AOD productivity and lower its energy and material consumption as well as the manufacturing cost.Book Part Citation - Scopus: 32Language of Response Surface Methodology as an Experimental Strategy for Electrochemical Wastewater Treatment Process Optimization(Elsevier, 2022) Gören, Ayşegül Yağmur; Recepoğlu, Yaşar Kemal; Khataee, AlirezaThe availability and accessibility to safe and secure water resources are the key technological and scientific concerns of global significance. As a result of water scarcity worldwide, wastewater treatment and reuse are considered viable options to replace freshwater resources in agricultural irrigation and domestic and industrial purposes. A significant need for clean water has promoted the invention and/or enhancement of several electrochemical wastewater treatment (EWT) processes. Optimization of the process variables plays a crucial role in wastewater treatment to enhance technology performance, considering removal efficiency, operating cost, and environmental impacts. These processes are fundamentally complex multivariable, and the optimization through conventional methods is unreliable, inflexible, and time- and material-consuming. In this perspective, response surface methodology (RSM) appears to be a beneficial statistical experimental strategy for the performance optimization of the EWT process. This model could be utilized for the optimization and analysis of the individual and/or combined effects of operational variables on the treatment process to improve the system performance. Furthermore, this model provides a number of information from a slight number of experimental trials. In this chapter, a summary and a discussion are presented on the RSM model used in the electrochemical wastewater treatment processes to overcome process crucial challenges toward the optimization and modeling of process parameters. It provides a potential model to enhance the various types of wastewater treatment process performance with effective optimization. Overall, it is described that the RSM model can be used in EWT processes to find the optimum conditions.Article Citation - WoS: 52Citation - Scopus: 54Development of Si Doped Nano Hydroxyapatite Reinforced Bilayer Chitosan Nanocomposite Barrier Membranes for Guided Bone Regeneration(Elsevier, 2021) Tamburacı, Sedef; Tıhmınlıoğlu, FundaGuided Bone Regeneration (GBR) is a widely used process for the treatment of periodontal defects to prevent the formation of surrounding soft tissue at the periodontal defect and to provide hard tissue regeneration. Recently GBR designs have focused on the development of resorbable natural polymer-based barrier membranes due to their biodegradability and excellent biocompatibility. The aim of this study is to fabricate a novel bilayer nanocomposite membrane with microporous sublayer composed of chitosan and Si doped nanohydroxyapatite particles (Si-nHap) and chitosan/PEO nanofiber upper layer. Bilayer membrane was designed to prevent epithelial and fibroblastic cell migration and growth impeding bone formation with its upper layer and to support osteogenic cell bioactivity at the defect site with its sublayer. Microporous and nanofiber layers were fabricated by using freeze-drying and electrospinning techniques respectively. The effect of Si-nHap content on the morphological, mechanical and physical properties of the composites were investigated using SEM, AFM, micro-Ct, compression test, water uptake capacity and enzymatic degradation study. Antimicrobial properties of nanocomposite membranes were investigated with tube dilution and disk diffusion methods. In vitro cytotoxicity of bilayer membranes was evaluated. Saos-2 and NIH/3T3 proliferation studies were carried out on each layer. In vitro bioactivity of Saos-2 and NIH/3T3 cells were evaluated with ALP activity and hydroxyproline content respectively. Results showed that Si-nHap incorporation enhanced the mechanical and physical properties as well as controlling biodegradability of the polymer matrix. Besides, Si-nHap loading induced the bioactivity of Saos-2 cells by enhancing cell attachment, spreading and biomineralization on the material surface. Thus, results supported that designed bilayer nanocomposite membranes can be used as a potential biomaterial for guided bone regeneration in periodontal applications.Conference Object Hidrofobik İlaç Taşıyıcısı Olarak Akrilik Yıldız Blok Kopolimerler(Institute of Electrical and Electronics Engineers Inc., 2009) Genç, Gözde; Batıgün, Ayşegül; Bayraktar, Oğuz; Altıntaş, Özcan; Tunca, Ümit; Hizal, GürkanAmphiphilic poly(methyl methacrylate)-b-poly(acrylic acid) (PMMA-b-PAA) copolymers with 4 and 6 arms were synthesized by Atomic Transfer Radical Polymerization (ATRP). The polymers were characterized by GPC, H-NMR and FTIR analysis. Polymer samples synthesized at various molecular weights between 18-80 kDa were investigated in terms of maximum loading capacity and critical micelle concentration by fluorescence spectroscopy. 4 arm PMMA-b-PAA (MW 30 kDa) was loaded with hydrophobic model drug indomethacin with an extremely high drug loading efficiency (22.5% drug content). Drug loaded polymer formed a stable and biodegradable complex in aqueous medium.Conference Object Development of Functional Materials for Sirna Delivery and Neural Tissue Engineering(AIChE, 2015) Uz, Metin; Alsoy Altınkaya, Sacide; Mallapragada, Surya K.The current nonviral siRNA delivery systems in the literature face many problems such as, cellular entry, endosomal escape and efficient siRNA release. Considering this motive, we developed gold nanoparticles (AuNPs) and temperature/pH responsive pentablock copolymer based siRNA delivery systems to address these problems. The temperature and pH responsive cationic and amphiphilic pentablock copolymers, which were consisted of the temperature responsive Pluronic F127 middle block constructed by PEO-PPO-PEO ((poly(ethyleneoxide)-block-poly(propyleneoxide)-block-poly(ethyleneoxide))) blocks contributing cellular entry through temperature responsive micellization and pH responsive cationic PDEAEM (poly(2-diethylaminoethyl methacrylate)) end blocks facilitating nucleic acid condensation and endosomal escape, were used for the first time in the development of polyplex and AuNP based multicomponent siRNA delivery systems (MCSs). The results indicated that systems managed to protect siRNA from external effects, maintain the system stability, facilitate cellular entry and enhance endosomal escape. It was noted that the transfection efficiency of the MCSs, which were boosted by the presence of cleavable disulfide bond, was ~15% higher than the commercial product RNAiMax while the efficacy of polyplexes alone were similar to the RNAiMax.Conference Object Solution of the Non-Linear Poisson Boltzmann Theory for the General Case of Dissimilar Double Layers(2006) Polat, MehmetCalculation of the surface potentials, surface charges or electrostatic pressure for interacting colloidal particles is exceedingly important in mineral processing, environmental engineering, ceramic sciences, etc. Such calculations require solving the non-linear Poisson-Boltzmann theory at each plate separation. Though approximate analytical solutions of this theory are available for simplified cases, a general, but compact analytical solution is yet to be developed. A solution with no restrictions on surface potentials or charges is developed in this paper. The expressions developed are straightforward and require as input only the surface potentials at infinite separations.
