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Article Citation - WoS: 9Citation - Scopus: 9Experimental and Modeling Studies of a High-Temperature Electrochemical Hydrogen Compressor(Pergamon-elsevier Science Ltd, 2024) Durmus, Gizem Nur Bulanik; Kuzu, Cemil; Devrim, Yilser; Colpan, C. OzgurSome non-technical factors such as economics and logistics prevent hydrogen (H2) tech-nologies from becoming more widespread in daily life. Today, the prevalence of H2 tech-nologies requires new technological developments. Electrochemical hydrogen compressors (ECHC) are of great interest due to their ability to pressurize and purify in one step. In this study, the electrochemical H2 compression performance of high phosphoric acid (PA) doped poly 2,2-m-phenylene-5,5-benzimidazole (PBI) membrane-based HT-ECHC under high temperature and non-humid conditions was investigated through both an experimental and a numerical approach. The H2 compression capacity of HT-ECHC at different operating voltages was examined by performance tests at 160 degrees C, and it was determined that the electrochemical compression performance increased with increasing operating voltage. It was observed that the current density values also increased with increasing voltage, and it was determined that a current density of 61.2 A was obtained at 1 V. As a result of the tests, H2 was successfully compressed from atmospheric pressure to 60 bar by HT-ECHC without any gas leakage. The results of the developed model were compared with the experimental performance test data, and the variation of molar flow, cell voltage, and cell efficiency over time was examined. It has been determined that the back diffusion from the cathode to the anode in the cell increases with the increasing operating voltage of HT-ECHC and therefore the cell efficiency decreases. It has been evaluated that the developed model and experimental results are in good agreement. (c) 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.Article Citation - WoS: 17Citation - Scopus: 18Optimal Design and Technoeconomic Analysis of On-Site Hydrogen Refueling Station Powered by Wind and Solar Photovoltaic Hybrid Energy Systems(Pergamon-elsevier Science Ltd, 2025) Ozturk, Reyhan Atabay; Devrim, YilserIn this study, a grid-connected on-site hydrogen filling station (HRS) integrated with renewable energy systems is designed and examined for different daily hydrogen refueling capacities. The installation location of the HRS is selected in Izmir (Turkey) and daily solar radiation and wind speed data are used in the calculations. The HRS station was integrated with a hybrid energy system using photovoltaic panels (PV), wind turbine (WT) and PV/ WT and five different daily refueling scenarios were investigated. A techno-economic analysis is conducted for the designed HRS system, considering the initial investment capital, installation and operating costs. The levelized cost of hydrogen (LCOH) is evaluated according to different refueling capacity scenarios, periods of operation and renewable energy installation capacities. The lowest LCOH is obtained as 4.5 /kg H2 in the PVintegrated HRS system for a 20-year investment scenario. The results prove the suitability of the HRS system for integrating renewable energy in the identified region. It is recommended to integrate analytical models for the system components to increase the reliability of the design and optimization process in future planned studies.Article Citation - WoS: 5Citation - Scopus: 5Performance Analysis of a Gas-To System Based on Protonic-Ceramic Electrochemical Compressor(Pergamon-elsevier Science Ltd, 2023) Baniasadi, Ehsan; Ghojavand, Fateme; Colpan, Can Ozgur; Devrim, YilserIn this study, two scenarios are considered to evaluate the performance of a protonic ceramic electrochemical hydrogen compressor (EHC) and reformer integrated with a pro-ton exchange membrane fuel cell (PEMFC). First scenario includes integration of an EHC with PEMFC and in the second scenario, steam methane reforming (SMR) is replaced by an EHC. Results show that the highest energy and exergy efficiencies of the system in the first scenario is achieved when the area-specific resistance (ASR) in EHC is 1.5 Ucm2. An in-crease in the working temperature of EHC causes a considerable rise in the exergy destruction and an increase of energy efficiency by 7% in the first scenario, while the temperature of the reformer affects the exergy destruction, negligibly. The parametric study indicates that the best value of the current density of PEMFC is 0.8481 A/cm2 and 0.8324 A/cm2 and the best current density of PEM-EHC value is 0.4468 A/cm2 and 0.11 A/cm2 in the 1st and 2nd scenarios, respectively. Under the same conditions, energy and exergy efficiencies for the first scenario are 61.63% and 54.9% and for the second scenario are 42.48% and 14.61%, respectively.(c) 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.Review Citation - WoS: 42Citation - Scopus: 57Drawing the Big Picture of Games in Education: a Topic Modeling-Based Review of Past 55 Years(Pergamon-elsevier Science Ltd, 2023) Ekin, Cansu C.; Polat, Elif; Hopcan, SinanThe literature of games in education has a rich and multidisciplinary content. Due to the large number of studies in the field, it is not easy to analyze all relevant studies. There are few studies exploring the big picture of research trends in the field. For this reason, the purpose of this study is to examine longitudinal trends of game-based research in education using text mining tech-niques. 4980 publications were retrieved as an experimental dataset indexed by the SCOPUS database in the period 1968 to mid-2021. The results include descriptive statistics of game-based research, trends of the research topics, and trends in the frequency of each topic over time. They show that the number of studies focusing on the use of games in education has increased, particularly since the 2000s when Internet use accelerated and became widespread. Approxi-mately 70% of all the studies were conducted in the last 10 years. One third of the studies is related to the main topic of game-based learning. It is significant that in the last three decades the topic of serious games has been among the top three trends. Considering usage acceleration of the topics, the highest values belong to game-based learning, serious games and student science games, in that order. The findings of this study are expected to guide the field by providing a better understanding of the trends of games in education and offer a direction for future research.Article Citation - WoS: 11Citation - Scopus: 12Expanding the Role of Exosomes in Drug, Biomolecule, and Nanoparticle Delivery(Pergamon-elsevier Science Ltd, 2025) Saka, Ongun Mehmet; Dora, Devrim Demir; Kibar, Gunes; Tevlek, AtakanExosomes are nanoscale extracellular vesicles released by diverse cell types, serving essential functions in intercellular communication and physiological processes. These vesicles have garnered considerable interest in recent years for their potential as drug delivery systems, attributed to their natural origin, minimal immunogenicity, high biocompatibility, and capacity to traverse biological barriers, including the blood-brain barrier. Exosomes can be obtained from diverse biological fluids, rendering them accessible and versatile vehicles for therapeutic medicines. This study emphasizes the burgeoning significance of exosomes in drug administration, concentrating on their benefits, including improved stability, target selectivity, and the capacity to encapsulate various biomolecules, such as proteins, nucleic acids, and small molecules. Notwithstanding their potential applications, other problems remain, including as effective drug loading, industrial scalability, and the standardization of isolation methodologies. Overcoming these hurdles via new research is essential for fully harnessing the promise of exosomes in therapeutic applications, especially in the treatment of intricate diseases like cancer and neurological disorders.Article Citation - WoS: 3Citation - Scopus: 4Selecting Facility Location of Gendarmerie Search and Rescue (gsr) Units; an Analysis of Efficiency in Disaster Response(Pergamon-elsevier Science Ltd, 2024) Abdulvahitoglu, Adnan; Varu, Danismet; Macit, IrfanDisasters, referred to as events that result in physical, economic, and social losses for individuals and disrupt the daily activities of human communities, necessitate ongoing preparedness due to their unpredictable nature. Swift response during and after a disaster is crucial for preserving human life. Hence, it is imperative to initiate planning immediately following a disaster to ensure readiness for various tasks. Given these factors, search and rescue units must carefully select a base location that enables them to promptly reach affected areas. Disasters exhibit unique characteristics across different regions of T & uuml;rkiye. While some regions are prone to earthquakes, others face the risks of landslides, avalanches, or floods. Consequently, the required measures for disaster management vary from region to region. Nevertheless, when the term "disaster" is mentioned in T & uuml;rkiye, earthquakes often come to mind due to their frequent occurrence and significant impact. The Gendarmerie Search and Rescue (GSR) units have been actively responding to these earthquakes, renowned for their exemplary institutional discipline and working methods. This study aims to examine the operations and deployment locations of GSR units, which play a crucial role in mitigating the impact of frequent earthquakes in T & uuml;rkiye, utilizing a SWOT analysis. Additionally, a Multi-Criteria Decision Making-based mathematical model will be employed to optimize task activities and to select the most suitable facility locations for GSR units. The use of mathematical modeling in this context ensures that GSR units are strategically positioned to maximize their operational effectiveness and minimize response times. The results will be evaluated through sensitivity analysis.Article Citation - WoS: 2Citation - Scopus: 2Thermoeconomic Analysis of an Integrated Membrane Reactor and Carbon Dioxide Capture System Producing Decarbonized Hydrogen(Pergamon-elsevier Science Ltd, 2025) Atak, Yagmur Nalbant; Ince, Alper Can; Colpan, C. Ozgur; Iulianelli, Adolfo; Serincan, Mustafa Fazil; Pasaogullari, UgurIn this study, a novel thermo-economic analysis on a membrane reactor adopted to generate hydrogen, coupled to a carbon-dioxide capture system, is proposed. Exergy destruction, fuel, and environmental as well as purchased equipment costs have been accounted to estimate the cost of hydrogen production in the aforementioned integrated plant. It has been found that the integration of the CO2 capture system with the membrane reactor is responsible for the reduction of the hydrogen production cost by 12 % due to the decrease in environmental penalty cost. In addition, the effects of operating parameters (steam-to-carbo ratio and biogas temperature) on the hydrogen production cost are investigated. Hence, this work demonstrates that the latter can be decreased by approximately 2 $/kgH2 when steam to carbon ratio increases from 1.5 to 4. The analyses reveal that steam-tocarbo ratio increases exergy destruction cost, affecting consequently also the hydrogen production cost. However, from a thermodynamic point of view, it enhances the hydrogen production in the membrane reactor, mutually lowering the hydrogen production cost. It has been also estimated that a decrease in the biogas inlet temperature from 450 to 400 degrees C can reduce the hydrogen production cost by 7 %. This study demonstrates that the fuel cost is a major economic parameter affecting commercialization of hydrogen production, while exergy destruction and environmental costs are also significant factors in determining the hydrogen production cost.Review Citation - WoS: 1Citation - Scopus: 1Diagnostic Use of Circulating Cells and Sub-Cellular Bio-Particles(Pergamon-elsevier Science Ltd, 2024) Tevlek, AtakanIn the bloodstream or other physiological fluids, "circulating cells and sub-cellular bio-particles" include many microscopic biological elements such as circulating tumor cells (CTCs), cell-free DNA (cfDNA), exosomes, microRNAs, platelets, immune cells, and proteins are the most well-known and investigated. These structures are crucial biomarkers in healthcare and medical research for the early detection of cancer and other disorders, enabling treatment to commence before the onset of clinical symptoms and enhancing the efficacy of treatments. As the size of these biomarkers to be detected decreases and their numbers in body fluids diminishes, the detection materials, ranging from visual inspection to advanced microscopy techniques, begin to become smaller, more sensitive, faster, and more effective, thanks to developing nanotechnology. This review first defines the circulating cells and subcellular bio-particles with their biological, physical, and mechanical properties and second focuses on their diagnostic importance, including their most recent applications as biomarkers, the biosensors that are utilized to detect them, the present obstacles that must be surmounted, and prospective developments in the domain. As technology advances and biomolecular pathways are deepens, diagnostic tests will become more sensitive, specific, and thorough. Finally, integrating recent advances in the diagnostic use of circulating cells and bioparticles into clinical practice is promising for precision medicine and patient outcomes.Article Citation - WoS: 16Citation - Scopus: 18Developing an Infrared-Assisted Solar Drying System Using a Vertical Solar Air Heater With Perforated Baffles and Nano-Enhanced Black Paint(Pergamon-elsevier Science Ltd, 2023) Tuncer, Azim Dogus; Amini, Ali; Khanlari, AtaollahIn the present study, it is aimed to improve the performance of a solar drying system (SDS) utilizing ZnO nano-enhanced absorber coating and infrared heating system. In the first stage of this work, different geometrical configurations of the main heating system of the SDS which is a vertical solar air heater (VSH) have been numerically analyzed. According to the numerical findings, VSH with perforated type baffles gave the best performance results. Then, the determined configuration has been manufactured and combined with a drying chamber. Moreover, two other modifications have been applied to the system including an infrared heater and nano-enhanced black paint. In other words, the experimental part of this research contains three SDS types including a conventional SDS, a SDS with infrared heater and a SDS with infrared heater and ZnO nano-enhanced absorber coating (combined usage of two modifications). The mean thermal and exergetic efficiencies of the VSH analyzed within the scope of this work were attained between 53.54-65.12% and 9.94-14.32%, respectively. Moreover, combined use of infrared heater and nano-enhanced absorber coating material in the VSH decreased the drying time period as 43.75% when compared to the unmodified SDS.Article Citation - WoS: 10Citation - Scopus: 10Computational Insight of Lithium Adsorption and Intercalation in Bilayer Tic3(Pergamon-elsevier Science Ltd, 2024) Park, Jongee; Fatima, Syeda AfrinishLithium-ion batteries (LIBs) have gained significant attention owing to their long lifespan. However, these batteries offer unmatched energy storage capacity and suffer from restricted lithium-ion mobility within the electrodes. Here, we employ first-principles calculation to investigate the two-dimensional TiC3 bilayer material. The results exhibit a remarkably high specific capacity of 1277 mAh/g and a low diffusion energy barrier of 0.12 eV. The TiC3 bilayer is anticipated to show high electrical conductivity, maintaining its metallicity due to strong bonding with four Li atoms. Additionally, its high thermal and dynamic stabilities are expected to significantly enhance the battery performance. Notably, the AB stacking bilayer TiC3 experiences a mere 6.01 % increase in volume, considerably smaller compared to the 28 % increase observed in the SiC bilayer. This suggests that TiC3 bilayers remain intact even at the highest concentration of lithium adsorptions. We also explored the solidelectrolyte interface (SEI) formation at the outset of battery operation using reactive force field molecular dynamics simulation. The reactive products of SEI are nicely matched with previous experimental and theoretical findings. All these intriguing properties position the TiC3 bilayer as an exceptionally promising material for use in LIBs.