Chemical Engineering / Kimya Mühendisliği
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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.Correction Citation - WoS: 1Erratum: Bioactive Snail Mucus-Slime Extract Loaded Chitosan Scaffolds for Hard Tissue Regeneration: the Effect of Mucoadhesive and Antibacterial Extracts on Physical Characteristics and Bioactivity of Chitosan Matrix (Biomedical Materials (Bristol) (2021) 16 (065008) Doi: 10.1088/1748-605x(IOP Publishing, 2023) Perpelek, M.; Tamburaci, S.; Aydemi̇r, S.; Tıhmınlıoğlu, F.; Baykara, B.; Karakaşli, A.; Havitçioǧlu, H.The authors regret that some errors were identified in 'figures 12 and 13' on pages 14 and 15, in the published manuscript concerning fluorescence microscopy images of Saos-2 and SW1353 cells on scaffolds for 1 and 3 d of incubation. The fluorescence images in figures 12 and 13 were mistakenly used as duplicated due to the inadvertently mislabeling during the processing of files and integrating them into the final figures. Intensity data regarding corrected fluorescence images were also measured and corrected. The revised figures (figures 12 and 13) and their captions appear below. The authors apologize for this error and state that this does not change the scientific conclusions of the article in any way. (Figure Presented). © 2023 IOP Publishing Ltd.Book Part Citation - Scopus: 2Data Driven Leak Detection in a Real Heat Exchanger in an Oil Refinery(Elsevier, 2023) Yasmal, Aslı; Kuşoğlu Kaya, Gizem; Oktay, Emirhan; Çölmekci, Ceylan; Uzunlar, ErdalThis study focuses on implementation of a data-based leak detection method in a heat exchanger in a petroleum refinery. We have studied on the two real leakage cases in a heat exchanger in Izmit TUPRAS Refinery. Leaks are one of the major problems that occur in operations. The autoencoder (AE) method is implemented for leak detection. Reconstruction error is used as the leak indicator. In case of leakage, the reconstruction value is expected to increase. For both cases examined, the reconstruction error is found to be around 1-5 under normal operating conditions. On the other hand, reconstruction error is observed to change between 10 and 60 under the conditions with leakage. Besides, the AE is able to indicate the start of one leakage case before the process engineers noticed it. © 2023 Elsevier B.V.Article Citation - Scopus: 2A Comparative Assessment for Efficient Oleuropein Extraction From Olive Leaf (olea Europaea L. Folium)(Murat Yakar, 2023) Recepoğlu, Yaşar Kemal; Gümüşbulut, Gülin; Yüksel Özşen, AslıSince oleuropein has long been known in the health sector and is abundant directly in our country as the fourth largest olive producer, oleuropein, the predominant phenolic ingredient in olive leaves, was recovered in this study using Soxhlet extraction. The effects of different solvent types (acetonitrile, ethanol, methanol, and water), extraction period (4 cycles, 4 h, and 8 h), particle size (250-500 µm and 900-2000 µm), and pretreatment of olive leaves on the yield of oleuropein were examined to determine the maximum yield. A greater oleuropein yield was obtained when the particle size of olive leaves utilized for extraction was lowered. Furthermore, aqueous solvents revealed a higher yield of oleuropein than pure solvents and prolonging the extraction duration resulted in a significant increase in the amount of oleuropein extracted. On the other hand, pretreatment of olive leaves resulted in a reduction in oleuropein output. As a result, with 36% extraction efficiency in terms of olive leaf conversion, the highest oleuropein extraction yield was obtained as 13.35 mg g-1 dry leaf for 8 h of extraction time using olive leaves with a particle size of 250-500 µm and an 80% methanol solution as solvent. © Author(s) 2023.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.Article Citation - Scopus: 22Multi‑purpose Reverse Logistics Network Design for Medical Waste Management in a Megacity: Istanbul, Turkey(Springer, 2022) Balcı, Esin; Balcı, Sezin; Sofuoğlu, AysunIn the study, a multi-purpose reverse logistics network has been designed to create effectual management of medical waste (MW) generated in 39 districts of Istanbul, a heavily populated city, during the COVID-19 pandemic as well as that to be generated in the next decade. With the model, the medical waste management system in Istanbul is analyzed during the pandemic and for the next 10 years. The model attempts to integrate economic, environmental, and social objectives within the sustainable development goals. It aims to maximize the number of personnel and government earnings for the estimated MW of a megacity while minimizing the total fixed cost and the cost of carbon emissions and transportation. The results indicated that the existing facilities are sufficient for the treatment and disposal of MW generated even under pandemic conditions. However, the capacity of the sterilization facility could be insufficient to treat the estimated amount of MW in the next decade. Opening a sterilization facility near the sanitary landfill in Komurcuoda with a total management cost of 62,450,332 €/year would be an optimum solution for Istanbul MW. In comparison to the single-purpose model results, the multi-purpose model resulted in approximately 42,000 € more in total cost. Sensitivity analyses show that the amount of MW has the most significant effect on the total cost. This simple model created an effective MW management proposal for Istanbul, which can be a model for megacities.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.